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298 WILLIAM A. S. SARJEANT the knowledge of the distribution of dinoflagellates in Recent sediments and waters. Graham L. Williams initially studied the London Clay (Williams & Downie 19660, 6, c); he was later to become a pre-eminent figure in the research team of the Geological Survey of Canada. By that time, I was not only enlarging my studies to include French Jurassic assemblages, but also examining material from the Speeton Clay (early Cretaceous) of Yorkshire (1966a, 6, c, d, 1968; Neale & Sarjeant 1962) - studies abruptly terminated when my collections were destroyed in a fire at Nottingham University, where I was establishing my own research school. The first of my research students was David B. Williams, who studied the distribution of dinoflagellate cysts in the North Atlantic Ocean as indicators not only of water depth and proximity to shorelines, but also of oceanic circulation (Williams & Sarjeant 1967; Williams 1968). Roger J. Davey studied Chalk (Late Cretaceous) assemblages (1969, 1970); he and I were involved in collaborative taxonomic researches with Downie and Graham Williams (Davey et al. 1966; Davey & Williams 19660, b). When, towards the end of this period, I presented further papers at international meetings on dinoflagellate cysts as biostratigraphical indices (19676, 1970c), I had a much greater fund of information to draw upon. Though Downie continued to make personal contributions, his prime concern had shifted to the acritarchs (see Sarjeant 1999). The earliest of his Palaeozoic researches was on a Tremadocian (earliest Ordovician) assemblage (1958) from Shropshire, England, but soon they expanded to comprise Silurian microfloras from that county (1959, 1963), Early Cambrian and late Precam- brian acritarchs from Scotland and the Grand Canyon, Colorado (1962, 1969), and joint work with Wall on Permian acritarchs (Wall & Downie 1963). Downie's student J. Richard Lister completed a major study of Silurian acritarchs, presenting evidence for the dinoflagellate affinity of some of them (19700, 6); unfortunately, Lister's studies were destined never to be fully published. The most extensive work on Palaeozoic acritarchs during this period was in Russia. Naumova, in Moscow, and Timofeyev, in Leningrad, were the prime figures. Unfortu- nately both of them initially misinterpreted these marine planktonic organisms as being spores of terrestrial or marine plants. Naumova, in five papers covering Riphean (Late Protero- zoic) to Silurian assemblages (starting in 1949), never relinquished that concept. Timofeyev, perhaps the only distinguished male palynolo- gist of the USSR, consistently ignored Naumova's work and was overoptimistic in his reports of trilete marks on Early Palaeozoic specimens (Timofeyev 1955). Ultimately, however, he accepted that many of his forms were of planktonic character, initially naming them 'hystrichospheres' (Timofeyev 1956) and then adopting his own classification (see p. 297). His work was of variable quality but great importance; it is discussed in detail by Jankauskas & Sarjeant (2001). Other major contributors to acritarch research during this period included Francois Stockmans and his wife, Yvonne Williere, who described Belgian Silurian to Carboniferous assemblages in a series of papers (e.g. 1960), early accepting the acritarch concept (1963). Their work was to be followed up by further studies of Silurian assemblages by Francine Martin (1966, 1967), who also extended her research to Belgian Ordovician acritarchs (19690, b), and by Michel Vanguestaine, who initiated the study of Cambrian assemblages (1967, 1968). Jean Deunff published many accounts of Ordovician to Devonian assemblages, in particular from Brittany, France (1951, 19540, and later papers) but also from the Devonian of Canada (19546,1957,19610), from the Saharan region of Algeria (19616) and from Tunisia (1966). Fritz H. Cramer reported acritarchs widely from Spain and Canada (1964 and later papers; Cramer & Diez 1968, 1970), also using them to try to reconstruct the motions of continental plates in the Silurian (1970). Middle Triassic assemblages from Switzerland were described by Marita Brosius and Peter Bitterli (1961), while Permian and Triassic assemblages were reported from western Canada by Jansonius (1962) and from the Permian of Pakistan by myself (Sarjeant 19706). Paul Tasch's report of Permian hystricho- sphaerids from Kansas (1963) was always viewed dubiously and was ultimately discounted by Evitt (1985). In contrast, Francois Calandra's description (1964) of a tabulate dinoflagellate from the Late Silurian of Tunisia, Arpylorus antiquus, was considered sound and was long to remain the earliest undoubted record of that group (see Sarjeant 19786). An overall review of developments since 1970 is presented by Robert A. Fensome, James B. Riding and F. J. R. 'Max' Taylor (1996). Prasinophytes The taxonomic history of this group in the early post-War period was bound up with that of the 'hystrichospheres'. Up to 1952 only two genera, PALYNOLOGY 299 Tasmanites and Pleurozonaria, had been described. Within the ensuing 15 years, however, 14 additional genera were named. Three of these were described from the Silurian to Devonian of Brazil (Brito & Santos 1965; Brito 1965; F. W. Sommer & Norma M. van Boekel 1963) and another from the Devonian of Oklahoma (Wilson & Urban 1963). Further new genera were reported from the Carboniferous of Saudi Arabia (Hemer & Nygreen 1967); the Permian of Western Australia (Segroves 1967); the Early Jurassic of Germany (Madler 1963); and the Cretaceous to Tertiary of Western Aus- tralia, New Guinea and Svalbard (Cookson & Manum 1960). Two genera were named from the Palaeogene of Hungary (Kedves 1962, 1963; Krivan-Hutter 1963); one from the Tertiary of California (Norem 1955); another from the Miocene of Hungary (Hajos 1964); and the latest from the Neogene of Hungary (Nagy 1965). Of these, two (Pseudolunulidia and Quisquilites) are bean-shaped; the former is probably a synonym of the latter (Wilson, quoted in Muir & Sarjeant 1971). The others are all spheroidal, though often compressed to a disc shape, with walls variously porate: most appear likely to be junior taxonomic synonyms of Tasmanites, but this remains to be demonstrated. The number of species of Tasmanites itself likewise increased greatly during this period, in particular through work on the Devonian of the Amazon basin of Brazil by Sommer and van Boekel (Sommer 1953 and later papers; Sommer & van Boekel 1963; van Boekel 1963) and by Eisenack in Germany (1958&, 19636?). Again, it is likely that these names include many taxonomic synonyms. Eisenack (1958b) accepted that his own Leiosphaera solida was a taxonomic synonym of Tasmanites punctatus, rendering the generic name Leiosphaera redundant. He placed the thin-walled leiospheres instead into a new genus, Leiosphaeridia. Five years later, Madler set up the Order Tas- manales within his new Class Hystrichophyta (1963), incorporating both these morphotypes (see p. 297). Madler's proposal was at the outset redundant since, a year earlier, Wall (1962) had demonstrated the close similarity of Tasmanites to the reproductive bodies of the living algal genera Pachysphaera and Halosphaera. These two genera were placed by Wall into the Class Chlorophyceae. However, almost at the same time, the algologist T. Christiansen (1962) was subdividing that class, on the basis of differing life cycles; he erected the new Class Prasino- phyceae, which included both those modern genera. In recognition of Wall's work, Downie (1967) reallocated Tasmanites to that class. Elec- tron-microscope studies by Ulrich Jux (1968, 1969) subsequently confirmed Wall's work and Downie's action; in contrast, his joint suggestion that Norem's genus Tytthodiscus was a thecamoebian (Jux & Moericke 1965) has found few adherents. The characteristic porate walls of these prasinophytes find no parallels in the leiospheres. These remain an incertae sedis group, being most often placed into the acritarch sub- group Sphaeromorphitae. Two other genera, nowadays considered to be prasinophytes, were erected during this period. Cymatiosphaera, a spheroidal form patterned with polygonal meshes of variable height, had been named by Otto Wetzel (1933) but was only validated many years later by Deflandre (1954). The Danian (early Palaeocene) genus Pteros- permopsis W. Wetzel (1952) was so named since, from the outset, its close resemblance to the living alga Pterosperma was perceived. Eisenack (1972) was to claim, quite without justification, that the type of Wetzel's genus was unstudyable; he erected his own genus Pterospermella as sub- stitute. Though I have demonstrated the invalid- ity of Eisenack's premise (Sarjeant 1984a), the later, quite superfluous name continues in use. Both genera were treated as acritarchs during this period, being placed respectively into the acritarch subgroups Herkomorphitae and Ptero- morphitae. (For an excellent summary of later work on prasinophytes, see Guy-Ohlson 1996.) Scolecodonts During the petroleum exploration in the Devon- ian of Brazil, Frederico W. Lange (Fig. 34) reported articulated, as well as dispersed, scolecodonts on shale surfaces (1947,19490). Roman Kozlowski (1956), employing chemical extraction techniques, obtained further well-preserved jaw apparatuses from the Polish Ordovician. His method was used on a larger scale by Zofia Kielan Jaworowska (1961,1966); she concurred with her predecessors in considering dispersed scolecodonts to be normally incapable of precise systematic assignation. In her magnum opus on this group, Kielan-Jaworowska (1966) described many jaw apparatuses in detail and presented a preliminary phylogeny of certain groups. The microstructure of living and fossil scolecodonts was described by K. W. Schwab (1966). Their stratigraphical range was expanded by reports of Permian scolecodonts from Germany by H. Kozur (1967) and from Poland by H. Szaniawski (1968); the latter author also reported further finds in the Polish Ordovician 300 WILLIAM A. S. SARJEANT Fig. 34. Frederico Waldemar Lange (1911-1988) at a meeting of the Commission International sur le microflore du Paleozoique (acritarches), Bordeaux, France (photograph by the author, 25 November 1964). Fig. 35. Charles Collinson (photograph by the author. 10 September 1969). and Silurian (1970). Philippe Taugourdeau described Siluro-Devonian and Carboniferous forms from boreholes in the Algerian Sahara (1968). In 1970, Kozur attempted to integrate the two taxonomies - that for jaw apparatuses and that for individual scolecodonts. Jansonius and J. H. Craig (1971) considered his approach to be premature and it has dropped from use. However, the recognition of scolecodonts as being components of the proboscidal armatures ('jaws') of polychaete worms, and not of annelids, was by then universal. (For a useful summary of present knowledge, see H. Szani- awski 1996.) Chitinozoans It was their recognition as biostratigraphical tools by the French petroleum industry, and that industry's concern with discovering oil concentrations in Palaeozoic strata, which stimulated the enormous expansion of chitinozoan studies during this period. They were especially suitable for company purposes in that their simple morphology and definitive evolution meant that minimal training was required before a person could use them for dating samples. In a series of publications, Taugourdeau not only reported them from the Silurian of the Aquitaine basin, France (1961), the Ordovician of the United States (1965) and the Early Palaeozoic of the Algerian Sahara (Taugourdeau & B. de Jekhowsky 1960), but also suggested novel approaches to their description and classification (1966). He and others presented an annotated bibliography of chitinozoans (Taugourdeau et al 1967). Silurian chitinozoans were reported by P. M. Bouche (1965) from northern Nigeria, by Beju and N. Danet (1962) from Romania and by Cramer (1964,1967) from Spain. Jeanne Doubinger and Jacques Poncet (1964) recorded Devonian forms from France; Lange discovered them during the search for petroleum in the Brazilian Devonian (1949&, 1952); and R. I. Jodry and Donald E. Campau extolled their biostratigraphical value to US petroleum geologists (1961). Charles Collinson of the Illinois Geological Survey (Fig. 35) not only reported them from the Devonian of that PALYNOLOGY 301 state, but also wrote a valuable joint review of North American chitinozoans (Collinson & Schwalb 1955; Collinson & Scott 1958). Eisenack himself continued to work on the group he had discovered, in a series of papers that sometimes treated them separately, sometimes along with Palaeozoic acritarchs (1955, 1962, and later papers). Ordovician chitinozoans were reported by Frank H. T. Rhodes (1951) from Wales and by Georg Schultz (1967) and Sven Laufeld (1967) from Sweden. P. Richard Evans recorded them from Western Australia (1961), W. Anthony M. Jenkins from the Ordovician of England (1967) and Oklahoma (1969), and Wilson and Robert T. Clarke from the Early Carboniferous of that state (1960). D. L. Dunn described them from the Devonian of Iowa and Michigan (1959; Dunn & T. H. Miller 1964), Roger F. Boneham from the Middle Devonian of Ontario and Ohio, (1967,1969) and E. L. Gafford and Evan J. Kidson from the Permian of Kansas (1968) - rather doubtfully, since reworking was thought possible. In an extended study of the chitinozoans, Kozlowski (1963) pointed out that they occurred quite often as straight or spiral chains, linked aperture to base, side by side, or loosely attached within a sac-like cocoon. He noted also that some specimens of Cyathochitina have a spongy mass at the base, which perhaps served for attachment. The presence of a sac-like structure (the opisthosome) within the chamber of solitary or colonial forms, and of an apparently contractile structure (the prosome) within the neck, was also noteworthy. All these features needed to be taken into account when the affinity of the chitinozoans was considered. Eisenack (1962) and others considered that they were gastropod egg-cases (see Sarjeant 19926, p.501). Kozlowski (1963), although noting parallels in arrangement to polychaete and gastropod eggs, considered the structure of those eggs to be too dissimilar from that of chitinozoans to sustain any relationships; he concluded that the affinity of the chitinozoans remained obscure. Taugourdeau (1964) reported an Ancyrochitina containing a roughly spherical body, too large to pass out through the aperture; he felt that this indicated an encysted or reproductive stage but favoured the view (expressed earlier by Deflandre 1945) that they were an independent, extinct group. Jenkins (1970) noted the remarkable correspondence in distribution, and in relative diversity per horizon, between chitinozoans and graptolites, suggesting that they might represent the missing prosicular stage in graptolite development. Though this idea was ingenious, it was ultimately to prove incorrect (Cashman 1990; summary in Miller 1996). The classification of the chitinozoans was considered in a series of papers by Jan Jansonius (1964,1967,1969) but this, like their affinity, was destined to remain controversial. Other palynomorphs In the early post-War years, the algal genus Botryococcus received little notice. In the 1960s, however, it became the focus for increasing attention. Its presence in English Carboniferous rocks was reported by Alan E. Marshall and A. H. V. Smith (1964) and in US Early Tertiary deposits by Traverse (19556). A. C. Brown et al (1969) described the three physiological states: a green, active growth stage with straight-chain olefines; a brown to orange resting state 'of mul- berry habit' with high concentrations of unsatu- rated hydrocarbons; and a dark green, dormant stage with little hydrocarbon. The importance of Botryococcus as a source of oil was stressed in a series of papers (Maxwell et al. 1968; Brown et al 1969; Cane 1969; Knights et al 1970), while the contribution of bacterial action to the formation of torbanites and other oil-rich sediments was stressed by A. G. Douglas et al (1969). (For an account of subsequent studies, see Batten & Grenfell 1996.) The colonial genus Gloeocapsamorpha was so named by Zalessky (1917) because of its similarity to the modern cyanobacterium Gloeocapsa. There are indications that it might be a marine alga and, though the suggestion by Traverse (19556) and others that it was synonymous with Botryococcus is no longer accepted, its systematic position remains uncertain. It is an important component of Ordovician marine shales in the Baltic Basin of Estonia, being styled kukersite and mined as a source of fuel (Bekker 1921). It is present also in Baltic Silurian sediments (Eise- nack 1960); however, the report by Timofeyev (1966), from the Lower Sinian (Proterozoic) of China, is considered questionable. The explosion of work on this organism occurred after 1970; it is reviewed by Wicander et al (1996). Another colonial alga, Pediastrum, hitherto known only from freshwater deposits, was reported from Cretaceous strata by Evitt (19636); it is attributed to the Chlorococcales. Evitt also published a detailed study of the ophiobolids (1968); however, their affinity remains uncertain. Following the first report by Deane (1849), the acid-resistant linings of foraminiferal tests received virtually no attention for more than a century. When studies were renewed, they gave 302 WILLIAM A. S. SARJEANT rise initially to errors. John F. Grayson (1956) considered them to be composed of calcium fluoride and dismissed them as fortuitous byproducts of the palynological preparation process. This mistake was corrected indepen- dently by Otto Wetzel (1957) and Frederik H. van Veen (1957), who both demonstrated their organic composition. However, they were there- upon misinterpreted as a distinct group of foraminifera with small organic-walled tests, 'microforaminifera' (Wilson & Hoffmeister 1959). Edwin D. McKee, John Chronic and Estella B. Leopold (1959), who encountered them in sediments from a Pacific atoll, doubted this, wondering whether the microfossils might be separate species, dwarfs or juveniles of larger species, or the remains of larger forms whose earliest chambers possessed organic linings. Experiments in which foraminiferal shells were dissolved in dilute acid showed the latter alternative to be correct (see Sarjeant 19926, pp. 507, 508). A first classification of foraminiferal linings was proposed by Ferenc Goczan (1962), who described five coiled types. Stefan Macko (1963) and M. H. Deak (1964) likewise proposed formal classifications, but this approach was rejected by Helen Tappan and Alfred R. Loe- blich Jr (1965), who preferred to place them instead into the existing classification of foraminifera. (For a history of subsequent developments, see R. P. W. Stancliffe 1996.) Little attention was paid to melanosclerites during this period. Eisenack (1963c), who had elevated them to the status of an Order Melanoskleritoitidea incertae sedis, described two new genera and reported further discoveries in 1971. New forms were described by Hanna Gorka (1971) from the Polish Ordovician and by R. Pichler (1971) from the German Devonian. However, no progress was to be made in their interpretation until the 1990s (see Cashman 1996). Three other groups characterized during this period - the 'pyritospheres' of Love (1958), the 'anellotubulates' of Otto Wetzel (1967) and the 'linolotypes' of Eisenack (1962) - have been subsequently shown to be pseudofossils, arti- facts of bacterial action or chemical processing (see Love 1962; Sarjeant 19926, pp. 513-514; Miller & Jansonius 1996). In contrast, several hitherto undescribed types of microfossils were distinguished for the first time, including arthro- pod cuticular fragments (Eisenack 1956; W. D. I. Rolfe 1962; Taugourdeau 1967), early growth stages of graptolites (Eisenack 1959, 1971) and possible eggs of polychaetes (Kozlowski 1974). Studies of Precambrian palynomorphs were begun by Lucien Cayeux (1894), who reported what he believed to be radiolarians from the Brioverian (late Precambrian) of Brittany, France. Deflandre (1949) showed this to be erroneous, considering instead that the Briover- ian forms were hystrichospheres. Raimond Hovasse (1956) reported Precambrian forms from the Ivory Coast. Subsequent studies by Maurice J. Graindor (1956, 1957), and by Deflandre himself (1955, 1957) resulted in the recognition of further taxa; all would later be called acritarchs. It was Timofeyev who discovered the rich Sinian and Riphean (Late Precambrian) microfloras of eastern Europe, western Russia, Ukraine and China (1959,1966,1969,1973; Tim- ofeyev et al. 1976). Most of the microfossils he reported were of quite large size (up to 1 mm in cross-measurement), spheroidal to ovoidal, with single or double walls and a reduced ornament. Since their affinity is questionable, they have usually been placed into the acritarch subgroups Sphaeromorphitae and Disphaeromorphitae. Timofeyev's studies were extended by N. A. Volkova (1968, 1969); his work is assessed by Jankauskus & Sarjeant 2001. A much more diverse palynoflora was reported by J. William Schopf (1968), the son of James Schopf, from the Late Precambrian Bitter Springs Formation of central Australia. This included cyanobacteria and a variety of other types of solitary or chain-forming organisms, as well as solitary forms doubtfully compared with simple dinoflagellates. The first record of earlier Precambrian micro- organisms came with the examination by Elso S. Barghoorn and M. A. Tyler (1962, 1965) of cherts from the Palaeoproterozoic Gunflint For- mation of southern Ontario, Canada. The Gun- flint microflora includes filaments (Gunflintia), ellipsoidal structures (Huroniospora) and a variety of other morphotypes. Subsequently, in co-operation with Schopf, Barghoorn reported 'three billion year old' micro-organisms from the Precambrian of South Africa (Barghoorn & Schopf 1966; Schopf & Barghoorn 1967). Despite the excitement caused by these discoveries (e.g. Cloud 1965), serious work on Pre- cambrian palynofloras was to continue at only a slow pace until the 1980s. (Subsequent discoveries are reviewed by Knoll 1996.) General developments in palynology (1945-1970) Before 1945, only two textbooks had been published in palynology, and both of these - PALYNOLOGY 303 Wodehouse's Pollen Grains (1935) and Erdtman's An Introduction to Pollen Analysis (1943) - were concerned almost wholly with actuopalynology, as was Kurt Faegri and Johs. Iversen's Textbook of Modern Pollen Analysis (1950). Erdtman's Pollen Morphology and Plant Taxonomy, published in four volumes (1952-1965; Erdtman & Sorsa 1971), was vastly larger in content, but scarcely broader in scope. Though there had been earlier newsletters for pollen specialists, there was no journal concen- trating on micropalaeontology, let alone on palynology, and there were no societies with a palynological focus. In consequence, papers on palynology were published in a wide variety of journals, mostly with a national, rather than an international, circulation. Illustration was always restricted, because of high costs; far too many published photographs, and even draw- ings, were so small as to render crucial features of morphology hard to discern. (My own earliest papers suffered badly from this particular blight; see Sarjeant 1959, 19606, c). Conse- quently, when the Palaeontological Association was formed in Great Britain in 1957, a particular aim was to produce a journal with ampler plates of higher quality. The plates in its journal Palaeontology, initially produced by the excellent (albeit now outdated) collotype process, were a revelation. In other regards, changes also did not come quickly. Improvements in microscopic equipment was slow. Eisenack took his photographs using a Leitz monocular microscope, to which he attached a box camera fashioned from a biscuit tin and furnished with glass negatives (see Gocht & Sarjeant 1983, p. 473). The camera which I fitted to the monocular petrological microscope for my own early studies (between 1956 and 1959) used film, but was not in other respects an improvement. The development in the early 1960s of such fine instruments as the various Zeiss photomicroscopes, in combination with improved techniques of palynological preparation (see Wood et al. 1996, for discussion), was an enormous advance. The first journal to deal specifically with microfossils was The Micropaleontologist, scarcely more than a newsletter and essentially without illustrations of quality. The launching, by the American Museum of Natural History in 1955, of the successor journal Micropaleontol- ogy marked a large step forward; however, though papers on palynology have appeared in that journal in increasing numbers, its emphasis has always been on microfossils with mineral- ized walls. A year earlier, Erdtman had launched in Sweden Grana Palynologica (now Grand), the first journal truly devoted to palynology; though featuring papers on other groups and themes from time to time, it has always been concerned primarily with pollen and spores and with actuopalynology. The coverage of the French journal Pollen et Spores, inaugurated in 1959, was virtually restricted to those themes. The first textbook in which palynomorphs, other than spores and pollen, gained extensive treatment was Erdtman's Handbook of Palynol- ogy (1969), to which I contributed on his invitation a 90-page 'Appendix' on other groups of palynomorphs. Yet this was still outside the main text - almost an afterthought. Much more bal- anced in treatment was a work published almost simultaneously, Aspects of Palynology (edited by Tschudy & Richard A. Scott 1969), in which tasmanitids and acritarchs were treated inciden- tally in several chapters, with a contribution on Precambrian and Palaeozoic microfloras by James M. Schopf and one on dinoflagellates and other marine palynomorphs by Evitt. The earliest national society was the Palyno- logical Society, formed in India in 1964. It published two journals, the Palynological Bulletin and the Journal of Palynology, both were started in 1965, combining under the latter title in 1972. Another Indian journal, The Palaeobotanist, continues to be published by the Birbal Sahni Institute of Palaeobotany and, in recent years at least, has frequently featured palynological papers. International gatherings of palynologists began with a semiformal meeting in Stockholm during the Vllth International Botanical Con- gress, with Erdtman as host. However, not till twelve years later did Kremp organize the First International Conference on Palynology, held in Arizona in 1962 with around 100 participants. At the Second International Conference on Paly- nology, staged in Utrecht, The Netherlands, in 1966, I was one of some 150 participants who contributed a paper which, we understood, would be published in a special conference volume. Instead, after we had surrendered the rights in our papers to the conference's organiz- ing committee, we were disconcerted to discover that they were to constitute the early parts of a new Elsevier journal, the Review of Palaeo- botany and Palynology (first published in 1967). Two useful bibliographies, of palaeopalynology by A. A. Manten (1969) and of actuopalynology by O. K. Hulshof & Manten (1971), were among its subsequent contents. I was also a participant in the gathering of 35 palynologists at Tulsa, Oklahoma, in December 1967, which inaugurated the second palynological society, the American Association of 304 WILLIAM A. S. SARJEANT Stratigraphic Palynologists (AASP; see Tra- verse & Sullivan 1983; Sarjeant 1998). It held its earliest annual meetings successively at Louisiana State University (LSU), Baton Rouge (1968), Pennsylvania State University (1969) and the University of Toronto (1970), the papers presented being published as volumes of the LSU series Geoscience and Man. In two papers by Manten (1968, 1970), the numbers of papers published in palynology and its subdisciplines were reviewed and the results presented in diagrammatic form. The absolute number had grown from less than 50 in 1916-1920 to around 5750 in 1961-1966; 34% of these papers were in English, 22% in Russian, 15.5% in German and 19.5% in French. To try to cope with this volume of publications, various compilative series were estab- lished. Potonie's seven-volume Synopsis der Gattungen der Sporae dispersae was the first (see p. 285). The Catalog of Spores and Pollen was begun by Gerhard Kremp and others in 1957; Kremp's Morphologic Encyclopedia of Palynol- ogy (1965) also remains useful. Deflandre and his wife, Marthe Deflandre-Rigaud (see Sar- jeant 19916), produced for many years a Fichier micropaleontologique generate which included dinoflagellates and acritarchs in its coverage; and Eisenack inaugurated in 1964 his Katalog der fossilen Dinoflagellaten, Hystrichospharen und verwandten Mikrofossilien. After 1970: changes and prospects If I had attempted to continue my history of palynology from 1970 to the present, this paper would have been at least thrice its present length. A number of new groups of microfossils have been recognized, in particular of green and blue-green algae. The classification of living and fossil dinoflagellates, long a cause of taxonomic problems and conceptual controversy, seems at last to have stabilized (see Fensome et al 1993). Though there have been immense advances in the understanding of the detailed structure and actions of living pollen and spores, through the work of John Rowley and others, the bases of nomenclature and classification for fossil pollen and spores remain in dispute and, indeed, the names sometimes change according to the level of the geological column which is under study, without any corresponding morphological changes. Off-shore records of palynomorphs from samples and cores had been published earlier (e.g. Wilson & Hoffmeister 1955; Stanley 19676, 1969; D. B. Williams 1968), but it was during this period that geology truly expanded into the oceans and palynology became a staple means of correlation of submarine sediments. This expansion was presaged by the work of Daniel Habib (1969, 1970). In particular, wide-ranging studies resulted from the international Deep Sea Drilling Project, in which Habib was an early participant (1972). Information is now available concerning the sequences of palynomorphs in all the world's oceans. All in all, this is an exciting period in the history of palaeopalynology; yet there are major problems. The importance of palynomorphs for biostratigraphical correlation and interpretation of past environments is recognized nowadays by oil companies, local and national geological surveys, and a variety of other bodies concerned with geological and environmental matters. This has generated an ever-growing flood of palynological literature, even though some companies and organizations still prefer to keep their results confidential and all too many theses and dissertations lie unpublished on university shelves. Enhanced processing methods and improved microscopical equipment have facilitated researches on the detailed structure of palynomorphs; phase contrast, Nomarski-interference contrast, confocal laser and scanning-electron microscopy have brought especially major advances. An inevitable corollary is the proliferation of taxa, some of them differentiated on such fine details as to mean that they can only be recognized when specimens are exceptionally well preserved and ideally oriented. (For example, some dinoflagellate generic names are determined entirely by the relative portion of certain small plates, the plates themselves being in most instances visible only with difficulty, if at all.) To keep abreast with an expanding nomenclature, such compilative works as the glossaries of dinoflagellate terminology (G. L. Williams et al. 1973,2000), the series of indices to dinoflagellate taxa begun by J. K. Lentin and Williams in 1973 and of acritarch and prasinophyte taxa by Fensome et al. (1990), and the continuation of the Eisenack 'Katalog' (Fensome et al. 1991 and later parts) are truly invaluable. Unfortunately, though a number of databases concerning pollen and spores are available - for example, Kremp's Palynodata and the AASP's Palydisks furnish valuable reference compilations, while the PalSys computer database of the Laboratory of Palaeobotany and Palynology, Utrecht, brings together figures and text of published taxa - no similarly authoritative analytical guides are cur- rently available to taxa of pollen and spores. Though Erdtman's Handbook was reissued in PALYNOLOGY 305 an enlarged edition (edited by Nilsson & Praglowski 1992), only one new single volume textbook on paleopalynology has appeared (Traverse 1988). Late in 1974, my textbook on Fossil and Living Dinoflagellates was published, the first on this theme. Subsequently, David L. Spector (1984) and Taylor (1987) published compilations of papers, largely on living dinoflagellates, and Evitt (1985) furnished an extended account of what he termed Sporopollenin Dino flagellate Cysts. A collection of important papers on all aspects of palynology, edited by Marjorie D. Muir and me, appeared in 1977. In 1998 the A ASP produced a comprehensive survey of information on Palynology: Principles and Practice, under the editorship of Jansonius and McGregor. The size of this work - three volumes and 1400 pages - is indicative of the growth of the field in the 31 years since the Association was formed. The circumstances of publication are changing. New journals devoted partially or entirely to palynomorphs have appeared: of these, the Revue de Micropaleontologie in France, the Revista Espahola de Micropaleontologia in Spain, the Journal of Micropalaeontology in the United Kingdom and the A ASP journal Paly- nology in the USA are the most important. Unfortunately, declining library budgets in universities and institutions, in combination with a growing tendency of companies to use consultants rather than employing full-time palynologists, has meant wholesale cancellations of journal subscriptions. This is already forcing some journals and serials to cease publication. (The Catalogue of Spores and Pollen foundered in 1985, Pollen et Spores in 1991, while certain other journals are nowadays appearing with dis- maying irregularity.) Computer accessing of data is certainly an available alternative, but the consequent high investment of funds and of personnel time mean that research by individuals outside large institutions is becoming increasingly difficult. It may be, indeed, that future researches will be done entirely outside the academic milieu. However, I trust not, since company and institutional requirements are inevitably focused so much on the financial bottom-line that little opportunity is afforded for the investigation of such matters as taxonomy and evolution, or even for inno- vations in technique, unless these are considered likely to yield future profits. Stronger associ- ations between universities and industry may offer a partial solution, even though such arrangements must, to some extent at least, com- promise academic freedom. The development of palynology: an overview Though the study of the dust that includes spores and pollen grains was begun quite early in the history of microscopy, it assumed importance only during the second half of the twentieth century. Before 1930, quite a lot had been learned concerning the reproductive function of these minute organic structures. Their significance in plant development and classification had been recognized and it had been realized that the inhalation of pollen could cause medically adverse effects. Spores had been recovered from sediments as ancient as the Devonian, as had prasinophytes (though the latter were not yet distinguished taxonomically). Dinoflagellate cysts, plus some still-mysterious spine-bearing microfossils, had been discovered in Mesozoic and Tertiary sediments. However, though the significance of pollen grains as climatic indices in Quaternary terrestrial sediments had been perceived, palynomorphs were in general receiving little attention from scientists at large. It was only after 1930 that their true geological potential came to be perceived. Yet progress was slow at first. Researches in Germany, Great Britain and the United States demonstrated the value of pre-Quaternary spores and pollen in the correlation of lignites and coals and showed their usefulness in the tracing of economic deposits underground. Investigations by company geologists were foreshadowing their use in the determination of subsurface structures, and thus in the search for oil and natural gas reservoirs. Even so, it was not until after World War II that their practical application was to become widespread. The use of pollen in the investigation of Quaternary deposits progressed faster, not merely as a tool for recognizing ancient environments but also for establishing relative dates of sediments and shell-beds. Before World War II, this was being done frequently; after that sad episode, it came to be done rou- tinely. The construction of pollen 'spectra' pro- vided visual references that could be employed by persons with minimal scientific training, facilitating greatly the work of prehistorians and archaeologists. New applications were developed: the allocation of dates to the spread of agricultural practices; elucidation of the diet of extinct animals and ancient humans; determination of the source and purity of honey; the identification of allergens and the demon- stration of a link between fossil spore concentrations and silicosis among coal miners; even 306 WILLIAM A. S. SARJEANT the use of palynomorphs as evidence in crime investigation. The study of marine palynomorphs lagged behind that of terrestrial forms. The 'xanthidia' - the spiny bodies that had puzzled Victorian microscopists - came to be renamed 'hystrichospheres', but their nature only began to be comprehended 30 years later. Even after the majority of post-Palaeozoic forms had been shown to be dinoflagellate cysts, the affinity of the residue - the acritarchs - remained long in question. (Indeed, it is only now being eluci- dated with any confidence). Certain other groups of marine palynomorphs - notably the prasinophytes and the scolecodonts - had been discovered before 1930, but attracted little study until several more decades had elapsed. The chitinozoans were first reported in the 1930s but, even though it now seems clear that they are an independent group of micro-organisms, their affinity is still being questioned. A variety of other groups of palynomorphs were discovered during that period and later, but most of them attract only intermittent study, even today. The employment of marine palynomorphs for purposes of biostratigraphical correlation really only began in the 1960s. Two factors favoured their use. Their distribution through a broader range of sediment types than those containing calcareous microfossils made them utilizable in samples from which foraminifera and ostracodes could not be extracted. Moreover, their much higher concentration meant that a single gram of sediment might yield in excess of 100 000 specimens, whereas a much larger sample would yield a very much smaller number of those larger microfossils. This was an especial advantage in making subsurface correlations of samples from small-diameter borehole cores or from sidewall cuttings. In consequence, the examination of marine palynomorphs came to be a basic means of dating samples in subsurface investigations by oil companies and consultants. The presence of palynomorphs of simple character in Early to Middle Proterozoic sediments proved interesting but not stratigraphically helpful, since morphological variation was limited and their evolution relatively slow. However, from the latest Proterozoic to the Late Devonian, the number and variety of acritarch taxa, and their quite rapidly changing morphology, has made them highly suitable for stratigraphical correlation. From earliest Ordovician to Devonian, the information thus gained can be supplemented by study of chitinozoans - a group whose simplicity of morphology and rapid evolution means that even an untrained beginner, if furnished with a correlation chart, can quickly assign dates to samples. In contrast, marine palynomorphs have, as yet, been only sparsely reported from Carbon- iferous and Permian strata. At those levels and in the later Devonian, correlation is best done using spores and pollen, and indeed, during those time intervals, continental sediments are both more widely exposed, and more economi- cally important, than marine sediments. That picture does not change in the earliest Triassic. In contrast, from the Middle Jurassic to the present, dinoflagellate assemblages are rich, varied and rapidly changing, making them ideal for surface and subsurface stratigraphical correlation. Moreover, though they do not character- ize depth zones in the oceans so clearly as do foraminifera, the dinoflagellates are being regu- larly used in the interpretation of marine environments. Even in the 1930s, only a handful of persons worldwide were engaged in palynological studies. By the 1950s, yes, the number had grown, but it remained small. Increasing recognition of the importance of palynology is made apparent by the immense growth in the memberships of the American Association of Stratigraphical Palynologists; this now has over 600 individual members, even though its membership is preponderantly North American and includes few medical practitioners of palynology. The last 70 years, then, have seen palynology grow from the esoteric pursuits of a few into the day-to-day activity of hundreds - from a scientific backwater into a mainstream of research. Whatever the future holds, the study of palynomorphs will surely continue to be of inestimable value to humanity. This paper grew out of an invitation from D. R. Oldroyd, to give a historical presentation on palynology at the International Geological Congress in Rio de Janeiro - a meeting in which, for reasons unimportant now, I felt unable to participate. The opportunity to write it came through an accident on fieldwork in Korea, which kept me housebound for several late- summer weeks. During that time, I was aided greatly by the daily visits and other assistance of my research assistant, J. W. C. Sharp. This research, and my other work, has been supported by Operating Grant No. 8,393 of the National Science and Engineering Research Council of Canada. It should be noted that the portraits contained herein are primarily those of spore-pollen palynologists. Portraits of dinoflagellate/acritarch specialists have been presented by me in an earlier paper (Sarjeant 1998). I should like to have featured more portraits of palynologists working on other groups of palynomorphs, but these were not readily available PALYNOLOGY 307 and time constraints prevented any prolonged search for them. References AGELOPOULOS, J. 1967. Hystrichospharen, Dinoflagel- laten undForaminiferen aus dem eozanen Kieselton von Heiligenhafen, Holstein, Mathematisch- naturwissenschaftlichen Fakultat der Eberhard- Karls-Universitat, Tubingen, Germany, 74 p. AfiRALi, B. 1963. Etude des microspores du Namurien a Taarlagzi (Bassin houiller d'Amasre, Turquie). Annales de la Societe geologique du Nord, 83, 145-159. ALBERTI, G. 1959a. Uber Pseudodeflandrea n.g. (Dinoflag.) aus dem Mittel-Oligozan von Nord- deutschland. Mitteilungen aus dem Geologischen Staatsinstitut Hamburg, 28, 91-92. ALBERTI, G. 19596. Zur Kenntnis der Gattung Deflan- drea (Dinoflag.) in der Kreide und im Alttertiar Nord-und Mitteldeutschlands. Mitteilungen aus dem Geologischen Staatsinstitut Hamburg, 28, 93-105. ALBERTI, G. 1961. Zur Kenntnis mesozoischer und alttertiarer Dinoflagellaten und Hystrichos- phaerideen von Nord-und Mitteldeutschland sowie einigen anderen Europaischen Gebieten. Palaeontographica, Series A, 116,1-58. ALPERN, B. & LIABEUF, J. J. 1966. Zonation paly- nologique du bassin houiller Lorrain. Zeitschrift der Deutschen geologischen Gesellschaft, 117, 162-177. BAKER, G. 1973. Dr. Isabel Clifton Cookson. In: GLOVER, J. E. & PLAYFORD, G. (eds) Mesozoic and Cainozoic Palynology: Essays in Honour of Isabel Cookson. Geological Society of Australia, Special Publication no. 4, i-x. BALME, B. E. 1952. The principal microspores of the Permian coals of Collie. Bulletin of the Geological Survey of Western Australia, no. 105,164-201. BALME, B. E. 1970. Palynology of Permian and Trias- sic strata in the Salt Range and Surghar Range, West Pakistan. In: KUMMEL, B. & TEICHERT, C. Stratigraphic Boundary Problems: Permian and Triassic of West Pakistan. University of Kansas Department of Geology Special Publication no. 4. University of Kansas Press, Lawrence, 305^53. BALTES, N. 1963. Dinoflagellate si Hystrichosphaeride cretacice din Platforma moezica. Petrol $i Gaze, 14, 581-597. BALTES, N. 1964. Albian microplankton from the Moesic Platform, Rumania. Micropaleontology, 13, 324-336. BALTES, N. 1965. Observatii asupra microflorei cretacice inferioare din zona R. Biraz. Petrol s,i Gaze, 16, 3-17. BARGHOORN, E. S. & SCHOPF, J. W. 1966. Micro-organisms three billion years old from the Precambrian of South Africa. Science, 152, 758-763. BARGHOORN, E. S. & TYLER, S. A. 1962. Microfossils from the Middle Precambrian of Canada. Abstracts, International Conference on Palynol- ogy, Tucson, Arizona, 1962. (Republished in Pollen et Spores, 4, 331). BARGHOORN, E. S. & TYLER, S. A. 1965. Micro- organisms from the Gunflint Chert. Science, 147, 563-577. BARSS, M. S. 1967. Illustrations of Canadian fossils: Carboniferous and Permian spores of Canada. Geological Survey of Canada, Paper, no. 67-11, 94pp. BATTEN, D. J. & GRENFELL, H. R. 1996. Botryococcus. In: JANSONIUS, J. & MCGREGOR, D. C. (eds) Palynology: Principles and Practice, Vol. 1, Prin- ciples. American Association of Stratigraphic Palynologists, College Station, Texas, 205-214. BEJU, D. 1969. Jurassic microplankton from the Carpathian foreland of Romania. Colloquium on the Mediterranean Jurassic, Budapest, 3-8 Septem- ber 1969,1-25. BEJU, D. & DANET, N. 1962. Chitinozoare siluriene din Platforma Moldoveneasca si Platforma Moezica. Petrol ?i Gaze, 13, 527-536. BEKKER, H. 1921. The Kuckers stage of the Ordovician rocks of NE Estonia. Ada et Commentationes Universitatis Dorpatensis, Series All, 1,1-91. BELSKY, C. V., BOLTENHAGEN, E. & POTONIE, R. 1965. Sporae dispersae der Oberen Kreide von Gabun, Aquatoriales Afrika. Palaontologische Zeitschrift, 39,72-83. BENNIE, J. & KIDSTON, R. 1886. On the occurrence of spores in the Carboniferous formations of Scot- land. Proceedings of the Royal Physical Society, Edinburgh, 9, 82-117. BHARDWAJ, D. C. 1962. The miospore genera in the coals of Raniganj stage (Upper Permian), India. Palaeobotanist, 9, 68-106. BINNEY, E. W. 1871. Observations on the structure of fossil plants found in the Carboniferous strata II. Lepidostrobus and some allied cones. Palaeonto- graphical Society Monographs, 24, 33-62. BLACKBURN, K. B. 1936. Botryococcus and the algal coals. I. A re-investigation of the alga Botryococ- cus braunii Kiitzing. Transactions of the Royal Society of Edinburgh, 58, 841-854. BOEKEL, N. M. VAN 1963. Uma nova especie de Tasmanites do Devoniano do Para. Anais da Academia Brasileira de Ciencias, 35, 353-355. BOLKHOVITINA, N. A. 1961. Fossil and recent spores of the Schizaeacae. Trudy Geologicheskogo Insti- tuta, Akademiya Nauk S. S. S. R., 40, 176 pp (in Russian). BOLKHOVITINA, N. A. 1968. The spores of the family Gleicheniaceae and their importance for strati- graphy. Trudy Geologicheskogo Instituta, Akademiya Nauk S. S. S. R., 186, 116 pp (in Russian). BONEHAM, R. F. 1967. Hamilton (Middle Devonian) Chitinozoa from Rock Glen, Arkona, Ontario. American Midland Naturalist, 178,121-125. BONEHAM, R. F. 1969. Middle Devonian (Erian) chitinozoan casts from silica, Lucas County, Ohio. Journal of Paleontology, 43, 527-528. BOSTOCK, J. 1819. Case of a periodical affliction of the eyes and chest. Medico-Chirurgical Transactions, 10,161-165. BOSTOCK, J. 1828. On catarrhus aestivus, or summer catarrh. Medico-Chirurgical Transactions, 12, 437^46. BOUCHE, P. M. 1965. Chitinozoaires du Silurien s.l. du [...]... ofMicropalaeontology, 10, 83 -93 SARJEANT, W A S 199 16 Sclerites, spicules and systematics: the researches of Marthe DeflandreRigaud ( 190 2- 198 7) Micropaleontology, 37, 191 - 195 SARJEANT, W A S 199 20 Gideon Mantell and the "Xanthidia" Archives of Natural History, 19, 91 -100 SARJEANT, W A S 199 26 Microfossils other than spores and pollen in palynological preparations In: NILSSON, S & PRAGLOWSKI, J (eds) Erdtman's Handbook... histories of these events (for example, Duff 197 9, 198 0; Ellis 199 6; Wimbledon 198 8; NCC 199 0) COLLECTING, CONSERVATION AND THE CULTURE OF BRITISH GEOLOGY In the 196 0s and 197 0s concern for the world's natural resources reflected the egalitarian or 'common ground' politics of ownership and responsibility, which had developed from the political Left Sustainability became the raison d'etre of the conservation... governments, and strong unions (Booth 199 5; Green 198 9; Healey 199 3; Overbeek 199 0; Smith 198 4) The earlier Conservative administration of Edward Heath had wished to deliver similar hard-line policies in 197 0, but its nerve failed By the time of Thatcher's fall in 199 0, the country had been transformed So much so, that when the Labour party emerged from its wilderness years, to return to government in 199 7,... 'Hystrichospheres' (acritarchs) and spores of the Wenlock Shales (Silurian) of Wenlock, England Palaeontology, 6, 625-652 DOWNIE, C 196 7 The geological history of the microplankton Review of Palaeobotany and Palynology, 1,2 69- 281 DOWNIE, C 196 9 Palynology of the Chuaria Shales of the Grand Canyon In: BASS, D L (ed.) Geology and Natural History of the Grand Canyon Region Guidebook to the 5th Field Conference... SARJEANT, W A S 199 8 From excystment to bloom? Personal recollections of thirty-five years of dinoflagellate and acritarch meetings Norges 322 WILLIAM A S SARJEANT teknisk-naturvitenskapelige universitet Vitenskapsmuseet Rapport botanisk, Series 199 8-2, 1-21 SARJEANT, W A S 199 9 Obituary: Charles Downie ( 192 3- 199 9) Acritarch Newsletter, no 15, 4-8 SARJEANT, W A S 2000 Charles Downie ( 192 3- 199 9) and his work... Texas, 93 3 -93 8 JONKER, F P 196 7 Palynology and The Netherlands Review of Palaeobotany and Palynology, 1, 31-35 Jux, U 196 8 Uber den Feinbau der Wandung bei Tasmanites Newton Palaeontographica, Series B, 124,112-124 Jux, U 196 9 Uber den Feinbau den Zystenwandung von Pachysphaera marshalliae Parke, 196 6 Palaeontographica, Series B, 125,104-111 Jux, U & MOERICKE, V 196 5 Tytthodiscus suevicus eine Thekamoebe?... Palaeobotany and Palynology, 1, 235-258 JEFFREY, E C 191 0 The nature of some supposed algal coals Proceedings of the American Academy of Arts and Sciences, 46, [273]- 290 JEFFREY, E C 191 4 On the composition and qualities of coal Economic Geology, 9, 732-742 JENKINS, W A M 196 7 Ordovician Chitinozoa from Shropshire Palaeontology, 10, 436^88 JENKINS, W A M 196 9 Chitinozoa from the Ordovician Viola and Fernvale... Stockholm, Forhandlingar, 5, 23-30 LISTER, T R 197 0a The method of opening, orientation and morphology of the Tremadocian acritarch, Acanthodiacrodium ubui Martin Proceedings of the Yorkshire Geological Society, 38, 47-55 LISTER, T R 197 Qb The acritarchs and Chitinozoa from the Wenlock and Ludlow series of the Ludlow and Millichope areas, Shropshire Part 1 Palaeontographical Society Monographs, The Palaeontographical... 196 7a Cretaceous spore and pollen assemblages from northern Alaska Review of Palaeobotany and Palynology, 1, 2 29- 234 STANLEY, E A 196 7!? Palynology of six ocean-bottom PALYNOLOGY cores from the southwestern Atlantic Ocean Review of Palaeobotany and Palynology, 2, 195 -203 STANLEY, E A 196 9 The occurrence and distribution of pollen and spores in marine sediments Proceedings of the First International... exhorting readers to save the planet The breadth of the perceived problem was enormous: agrochemicals and sustainability, lead levels in children and the proliferation of the car, the consequences of nuclear power and the social costs of coal extraction, industrial disease and the use of such materials as asbestos and heavy metals, population growth and problems of food supply, and much more All brought . expanded to comprise Silurian microfloras from that county ( 195 9, 196 3), Early Cambrian and late Precam- brian acritarchs from Scotland and the Grand Canyon, Colorado ( 196 2, 196 9), . England ( 196 7) and Oklahoma ( 196 9), and Wilson and Robert T. Clarke from the Early Carboniferous of that state ( 196 0). D. L. Dunn described them from the Devonian of Iowa and . Michigan ( 195 9; Dunn & T. H. Miller 196 4), Roger F. Boneham from the Middle Devonian of Ontario and Ohio, ( 196 7, 196 9) and E. L. Gafford and Evan J. Kidson from the Permian