Ostenfeld Diatoms 1910

DANMARK-EKSPEDITIONEN TIL GRØNLANDS NORDØSTKYST UNDER LEDELSE AF L MYLIUS-ERICHSEN BIND III 1906 — 1908 — INDHOLD Side I from North-East Greenland (N of 76° N lat.\ collected by the Danmark-Expedition 1906 1908, by C H Ostenfeld and Andr Lundager (Hertil Tavle I VI) The Insects of the Danmark-Expedition by Fritz Johansen and J List of Vascular Plants Nielsen III IV (Hertil Tavle VII— VIII) 33 Freshwater Algæ from the Danmark-Expedition to North-East Greenland by Borgesen (N of 76° N lat On the Marine Algæ from North-East Greenland, collected by the Danmark- ) Expedition, by L F 69 Kolderup Rosenvinge 91 Fungi Terrestres from North-East Greenland, collected by the Danmark135 Expedition, determined by C Ferdinandsen (Hertil Tavle IX) VI Systematic List of Fungi (Micromycetes) from North-East Greenland, col1908, determined by J Lind lected bj' the Danmark Expedition 1906 V 147 (Hertil Tavle Xl VII Hepaticea and Sphagnaceae from North-East Greenland, collected by the Danmark-Expedition 1906 1908, determined by C Jensen Mosses from North-East Greenland, collected by the Danmark-Expedition 1906—1908, determined by Aug Hesselbo (Hertil Tavle XI -XII) IX Lichens from North-East Greenland, collected by the Danmark-Expedition 1906 1908, determined by Olaf Galloe X Diatoms from North-East Greenland, collected by the Danmark-Expedition, determined bj' Ernst Østrup (Hertil Tavle XIII XIV) XI Marine Plankton from the East-Greenland Sea (W of 6° W long, and N of 73°3Ü' N lat.), collected during the Danmark-Expedition 1906—1908: I List of Diatoms and Flagellates by H Ostenfeld II Protozoa by H Ostenfeld III Peridinales by Ove Paulsen IV General remarks on the Microplankton by H Ostenfeld and Ove Paulsen XII Contributions to the Carboniferous Flora of North-Eastern Greenland by (Hertil Tavle XV- XVI) A G Nathorst XIII Some notes concerning the Vegetation of Germania Land, North-East Greenland, by Andr Lundager (Hertil Tavle XVII) XIV Acari by Ivar Tragårdh XV A Marine Dorylaimus from Greenland waters by Hjalmar Ditlevsen 163 VIII — 181 193 257 287 301 319 337 347 415 427 (Hertil Tavle XVIII) Bryozoa by G M R Levinsen (Hertil Tavle XIX-XXIV) XVII Report on the Porifera, collected by the Danmark-Expedition to NorthEast Greenland, by H V Bronsted (Hertil Tavle XXV -XXVI) XVIII The Alcyonaria of East-Greenland by Hegtor F E Jungersen XIX Actinaria and Zoantharia of the Danmark-Expedition by Oskar Carlgren XX The Marine Carboniferous of North-East Greenland and its Brachiopod Fauna by Karl A Grönwall (Hertil Tavle XXVII- XXX) XXI Quarternary Fossils, collected by the Danmark-Expedition, by Ad S Jensen XVI 169 431 473 485 505 509 619 38347 XI MARINE PLANKTON FROM THE EAST-GREENLAND SEA (W OF 6^W LONG AND N OF 73° 30' N LAT.) COLLECTED DURING THE "DANMARK EXPEDITION'^ I LIST OF DIATOMS 1906-1908 AND FLAGELLATES BY C H OSTENFELD 1910 XLIII 20 INTRODUCTION During the outward and homeward voyages of the Dan m arkin 190() and 1908 to and from N.E.Greenland the Expedition botanical Lundager has procured a large series of surface plankton by means of using tow-nets with collector samples af Mr A fine-meshed silk-gauze (Millergauze No 20) Also during the stay in Danma rks Havn (Denmark Harbour), Germania Land, 76°46' N Lat., were made Of late years several expeditions have crossed th(; Greenland Sea and brought home collections of plankton Therefore it was not likely that the plankton samples of the Danmark Expedition should give much new, especially not with regard to the samples taken in the open Greenland Sea east and south of the packice (drift-ice) The main interest must lie in the samples from the pack-ice itself and from the coastal Avater inside it, and further in the samples from Danmarks Havn I consequently limited my examination to the samples taken in these regions and have not wasted my time by examining the other samples which would have given only a feeble and chance knowledge of the plankton of the open Greenland Sea, »based, as it must have been, upon material from two crossings alone and both in July August It would have been of the highest value if the Expedition had taken samples at regular intervals, e g fortnightly, during the whole time of the stay in Danmarks Havn from August 1906 to July 1908, as we know very little of the seasonal changes in arctic coast-plankton The only source is Vanhoffen's investigations from Karajak Fjord 18°43' W Long., some collections — in West Greenland, ca, 70° N Lat., (Drygalski Expedition 1892—93), and it is easily understood that a comparison with those would have been much appropriate Unfortunately the collection from Danmarks Havn is very incomplete; it consists of some samples from the time between June 15"^ and September 10"' 1907 and a couple from July 21^* 1908 when the steamer left the harbour There is here lost a chance which, perhaps, will not come again for years 20* 260 Ostenfeld H As to the samples collected before and after the stay in Danmarks Havn, we have (1°) a fair collection from August 1906 and July 1908 taken in the more or less from off Koldewey Island ice-filled water along the coast N Lat.) to ca 78° N Lat., and (ca 76°30' an interesting collection from the traversing of the packAugust) During the homeward voyage in ice in both years (July July 1908 the samples from the coastal water and the pack-ice were taken with intervals of only one or a few hours, and a preliminary further (2*^) — examination soon showed that it was not necessary to work out more than a selected number In the following list I have enumerated the species of Diatoms and Flagellates, in another paper Mr OvE Paulsen will of fme-meshed silk-gauze larger organisms, Peridinians With regard to method with small open conical nets of the treat the Zooplankton the collecting is not well adapted to the capture of the metazoa; other samples taken by the Expedition with larger coarse-meshed nets and at different depths give better results; they will form the subject of papers by zoologists; it will, therefore, not be necessary to undertake a closer examination of the On surface samples in this respect at least the and Tin tinn odea, in a little separate the other hand, the require fine-meshed nets paper I shall Protozoa, for catching, enumerate the species of pro- tozoa found in the samples Finally Mr Paulsen and I in common will write on the surface plankton samples as a whole describing the general character of the plankton, the supposed origin of the organisms, etc under comparison with the hydrographical conditions and using the papers published by other planktologists on the plankton of the East Greenland Sea The list here given contains the names of all the plankton Diatoms and Flagellates determined from the samples, wdth quotaof the more important synonyms and figures, as well as of the general works (e g Gran's Diatoms in Nordisches Plankton) Critical remarks elucidated by figures are annexed to several species The list further gives the occurrence in the region, divided into the three above mentioned areas: Danmarks Havn, the coastal water and the pack-ice, and the tions of the first description, time for the presence in the plankton, as far as the scanty data allow At last the area of distribution mination did comprise 64 samples it is given summarily The exa- The littoral diatoms and the diatoms of the ice-floes are determined by Mr E ØSTRUP who publishes his results together with a treatment of the freshwater diatoms Marine Plankton from the East-Greenland Sea The following papers deal Avith 261 the phytoplankton from the East Greenland Sea: Broch, Plankton-tables, Hj., (1909): in D Damas et E.Koefoed, Le Plankton de la Mer du Grønland — Duc dOrleans: Croisière Océanographique accomplie bord de La Belgica dans la Mer du Grønland 1905 Bruxelles Cleve, p t., (1900): Report on the Plankton collected by the Swedish Expedition to Greenland ØSTRUP, , (1895): København — K Svenska Vet Akad Handl., Bd Marine Diatoméer fra Øst-Grønland Medd in 1899 — Hereto the two general works Gran, H H., (1904): Planktons Bd — III, (1905): Heft — be added om Stockholm Grønland, XVIII, : Die Diatomeen der arktischen Meere Fauna Arctica, herausgegeben von F Teil: Die Römer u Diatomeen des F Schaudinn, Jena Diatomeen Kiel u Leipzig ' 34, Nr — Nordisches Plankton, herausgegeben von K Brandt XIX Bacillariales (Diatoms) I A Centricæ Melosira Ag., 1824 ^ Melosira hyperborea (Grun.) Schult, in Engler A Prantl, Nat Pllanzenfam., I b, 189G, p 59; Gran, Norweg Nortti Polar Exp., Scientif Results, vol 4, No 11, 1900, p 52 pi 3, figs 11-15 M mimmuloides, var.'? hyperborea Grimow in V Heurck, Synopsis, pi 85, 3—4 figs The one of the most characterizing diatoms from the often occurs in practically pure mass cultures in holes in the ice-floes and in spaces between them Both in 1906 and in 1908 several samples from the pack-ice had this species as their main organism In most samples from July and August it had resting spores, answering well to the excellent figures in Gran's paper quoted above In October 1906 the samples from Danmarks Havn contained a few empty frustules, and in September 1907 the case was nearly the same, i e at that time the vegetation period was over In June (15*'') 1907 a sample collected in a crack of the species ice-floes land-ice is It shows us the species of frustules in in full growth, the chains consisting rapid division and with no trace of resting spores In the later half of July 1908 most of the samples from the coastal water and some from the inner part of the pack-ice contained in several of them even as common, and in nearly all samples sting spores as were present we must suppose that it Thus w^e get an idea of its it, re- life-cycle, winters as resting spores, probablj' frozen in the ice D ist ril), and tVom tiic \rctic nerilic species known from the arctic coast regions inner Baltic Thalassiosira Cleve, 1873 Thalassiosira Nordenskiöldii Cleve, Bih K Svenska Vet Akad Handl., Bd I, No 13, 1873, p 6, pi II, fig Gran, Norske Nord; ^ I tiave tlie Nord Plankton XIX consecutive order of genera and species given in Giỵan, Marine Plankton from the East-Greenland Sea havs-Exp., Protophyta, 1897, 1905, p 10, p 28, pi IV, fig 263 59; Nord Plankton XIX, fig This species is rather rare in the collection; it has been fonnd sample from the pack-ice in 190(5, in some samples from in a single Danmarks Havn in 1907 and 1908, and in several ones from the and the pack-ice in 1908, bnt never commonl}' The time where it "flowers" must be very short in these high latitudes as it has not been present in the June and July (first half) samples from Danmarks Havn No resting spores were seen July— Sep- coastal water tember D i strib Northern neritic species wioiely distributed along the coast regions of the northern countries Thalassiosira decipiens (Grun.) Jørgensen, Bergens Museums 1905, p 90, pi 6, fig 3; Gran, Nord Plankton, 1905 XIX, Skrifter, Ostenfeld, Wiss Ergeh Aral See Exp., VIII, 1908, p 144, T gelatinosa Hensen, Ber Komm Deutsch Meere, p 17, fig 10; pi 6, figs 1887, p 87 — 8; ; Coscinod isens excentriciis, ungsber naturw Ges piens Grunow Van in Found sparingly var.? decipiens Dresden, 1878, p 28, pi 0, Heurck, Synopsis, 1883, pi 91, Isis, in four Grunow, fig Sitz- 18; C deci- fig 10 samples from the outer margin of the pack-ice in 1906, not elsewhere July— Augusl )i Northern temperate species known from the coast regions of North and West-Europe, further from the Caspian and Aral Seas; not formerly found in arctic water, where it has not its home strib Thalassiosira hyalina (Grun.) Gran, Bibliotheca hot Heft 42, 1897, p 4, pi 1, figs 17 18; Nord Plankton XIX, p 17; E.Jørgensen, — Bergens Museums Norske Nordhavs Skrifter, 1905, p 96, pi VI, fig 5; Th Clevei Gran, Protophyta, 1897, p 29, pi 4, figs 60—62; Coscinodiscus hyalinns Grun in Cleve & Grunow, K Svenska VetAkad Handl., Bd 17, No 2, 1880, p 113, pi 7, fig 128; Grunow, Dial V E:xp., Franz Josefs Land, 1884, It is p 30, pi C, fig 28 I have found this species, so characonly very rarely and in a few samples from rather curious that teristic for the ice-floes, the pack-ice in August 1906 I) ist rib Arctic-neritic species known from the ice-floes and the coasts of the arctic Sea (reaching as far south as Stadt in Norwayl Thalassiosira gravida Cleve, Bih K Svenska Vet Akad 3, No 4, 1896, p 12, pi 2, figs 14-^16; Gran, Norske Nordhavs-Exp., Protophyta, 1897, p 28, pi 4, figs 57-58; Nord Plankton XIX, p 18, fig 12; Coscinodiscns subylobosus Cleve & Grun in Handl., Bd 22, afd: (irunow Dial v Franz Josefs Land, 1884, p 32, pi D, figs 19—20 — 264 H Ostenfeld In the samples from 1906 this species was only found twice and few specimens; also in 1907, in the samples from Danmarks Havn it was rare In 1908, on the other hand, it was common in many of the samples on the whole way from Danmarks Havn through the pack-ice In several samples the cells were very small, so-called hunger-specimens The resting spores (Coscinod subglobosus) were present in two samples (Septm 1907, July 1908) July —August September in very Distrib Northern neritic species widely distributed along the coast bordering the Arctic and North Atlantic Oceans and their tributaries Thalassiosira bioculata (Grun.) Ostenfeld, Bot of the Færoes, figs 120-121; Gran, Nord Plankton XIX, p 19, fig 14; Coscinodiscus b Grunow, Dial v Franz Josefs Land, 1884, p 30 et 56, pi , fig 30, pi D, figs 1-2 vol.2, 1903, Copenhagen, p 564, Single individuals were found in several of the samples from Chains are not seen and the species was not found in stage of strong growth July August September Danmarks Havn, — the coast water and also in the pack-ice — Distrib Northern neritic species known from the coast regions of the northern countries bordering the Davis Strait, northern Atlantic and Arctic Oceans Bacterosira Gran, 1900 Bacterosira fragilis Gran, Nyt Mag Naturvid., Christiania, 38, 1900, p 114; Nord Plankton, 1905, XIX, p 21; Lauder ia f Gran, Bibliotheca botanica Heft 42, 1897, p 18, pi 1, figs 12—14 Found very sparingly in samples from coast-water, not in the pack-ice July Danmarks Havn and the — August Distrib Arctic neritic species known from the coasts of the arctic Sea West- and East-(ireenland, Spitsbergen, Nova Zembla) and from the northern coast of Norway Lauderia Cleve, 1873 Lauderia glacialis (Grun.) Gran, Nyt Magaz Naturvid., Christiania, Bd 38, 1900, p Ill, pi 9, figs 10—14; Nord Plankton, XIX, p 23; Podosira hormoides, var glacialis Grunow, Diat Franz Josefs Land, 1884, p 56, pi C, fig 32; P glacialis Cleve, Bill K Svenska Vet Akad Handl., Bd 22, afd 3, No 4, 1896, p 12, pi 2, figs 17-20; Porosira g Jørgensen, Bergens Museums Skrifter, 1905, p 97, pi 6, fig Rare in the samples, found in Danmarks Havn and water, not in the pack-ice July in the coast — August Distrib Northern (sut^arctic) species known from the coastal regions of the arctic Sea and along the coasts of North-Europe (in winter) Marine Plankton from the East-Greenland Sea 265 Hyalodiscus Ehrbg., 1845 Hyalodiscus laevis Monatsber Berlin Akad WisGrunow, K Svenska Vet Akad Handl., Peragallo, Diatom marin, de France, pL 119, b^hrbg., sensch 1845, p 78; Cleve u Bd fig p 10, Cleve fig No 17, 20; H 1880, p 110; 12; fig Quart Journ Microsc sc, is p 1854, 179; pi 1, 1909, p 69 some samples from Danmarks Havn think, 1861, 7, Gran, Bibliotheca botanica, Heft 42, p 5, c, pi 119, fig Cfr Stockmayer, Annal, ; Hofmuseum, Wien, XXIII, I found sparingly a large diameter of the valve) of Hyalodiscus which, identical with Grans H siibtilis from Karajak Fjord On species {150 -\-ll the Peragallo, 19: naturh I Bailey, Smithson Contrib to knowledge, vol W Hendry, Grunow, u In 2, siibtilis fj other hand lœvis Ehrbg in I and cannot find any difference of valve between H siibtilis Bail Already Hendy (I.e.) has suggested marks in the proportion between the entire valve and the central part (umbilicus) as well as in the structure of the "umbỵ7/cus" arc value-less, and my here given figures (Fig 1) which that the distinctive Fig Hyalodiscus laevis Ehrbg 250 t m chosen as extremes will, taken together with the figures bv Peragallo, show that these characters are subject to great variability Therefore, I find it necessarj' to unite the two species in one to which H scoticus (^Kutz.) Grun must be referred as a dwarfy are variety — July — September D i strib Coast-species, not true plankton form, found scattered over the earth, especially in colder regions; often found in fossil depots Cosciiiodiscus Ehrbg., 1838 10 p Coscinodiscus centralis Ehrbg., Abhandl 129; Mikrogeologie, Museums i)l 18, fig 39 pi 22, fig Skrifter, 1905, p 93, pi 6, fig 1; ; Berl Akad., 1838, Jørgensen, Bergens Gran, Nord Plankton XIX, 272 in H Ostenfeld others they stand intermediate and in typical 127 c); thus the (fig f others again they were atlaniica has probably a very restricted value Distrib Arctic neritic species; known from tlie coasts of arctic counfound at Boliuslen, Scotland and in the Norwegian Sea tries; also (rarely) Chætoceras Ehrbg., 1844 Chætoceras atlanticum 20 Handl., Bd I, No Cleve, Bib K Svenska Vet Akad 13, lcS73, p 11, pi 2, fig Gran, Nord Plankton, XIX, ; fig 74 1905, p 64, found in several samples from Danmarks Havn, the coast water and the pack-ice, but always in single specimens July-September 1906-1908 This species is Distrib Widely distributed in the Atlantic also in the Antarctic Ocean; oceanic species Ocean and tributaries, its Chætoceras convolutum Castracane, Report of the Challenger Botany, II, 1886, p 78; Gran, Fauna Arctica, III, Heft 3, 1904, 21 Exp., p 530, fig ; Nord Plankton XIX, 1905, In the pack-ice this species it was was further found p 69 was dominant August 1906; in 1908 also present, tities in It in some samples from but not in greater quan- samples from the coastal water and from Danmarks Havn, but only sporadically and in single specimens Distrib Northern oceanic species, known from the Nortli Atlantic and the Antarctic Oceans Chætoceras criophilum Castracane, Report of the Challenger II, 1886, p 78; Gran, Fauna Arctica, III Heft 3, 1904, 22 Exp., Botany, p 532, fig 3; If we Nord Plankton XIX, 1905, follow Gran and the foregoing (1 species, i marks between this criophilum has none or a very the distinctive in c.) p 71 e rudimentary connecting zone and conuolatum a developed v,'ell very rare in the area, only some samples from the pack-ice, one in two were found specimens solitary It is rather unexpected that it is so rare, in 1906 and one in 1908 one, it results that this species is sea it is one of the characteristic and dominant species of the between Iceland and Jan Mayen as Distrib Northern oceanic species, widely distributed parts of the Atlantic and 23 its tributaries, further Chætoceras boréale ledge, vol 7, 1904, p 533, One and 1908 1854, p 8, fig 5, Bailey, 22 — 23; in the northern the Antarctic Smitsonian Contrib Gran, Fauna Arctic Nord Plankton XIX, to Ill, knowHeft 3, p 73 common species in the area was the dominant species in many samples from of the most it figs known from Both in 1906 the Medd om Gronl XLIII Nn 10 [Østrup] Tab XIV | s II m e 16 17 Aut del Marine Plankton from the East-Greenland coastal water and present also both in 273 Sea Danmarks Havn and in the inner border of the pack-ice hi August 1906 it was not uncommon at ca 13° W Long., and dominant in the samples taken along the Cape Amélie; in October 1906 some specimens were found in Danmarks Havn, but mostly empty fruSeptember 1907 sjngle specimens occurred in the stules In August samples from Danmarks Havn In July 1908 it was dominant in Danmarks Havn and from that place northwards along the coast until ca 78° N Lat., and it was further found in some samples a Koldewey Island coast from to — more eastwards, until ca 11° W Lat In some of the samples from August 1906 little and July 1908 taken in the coastal water (the temperature of the water being between -f- 0,5 and 4,2°) I often found chains in which the awns many of As the of the had cell-walls aborted shows, such a chain gets a rather fig curious aspect The two : latest divisions of the chain figured have produced new cells which bear no awns from the valves while the oldest division has given normally developed awns of which only the bases have been drawn At the places of the awns we find only small protuberances on the valves, and the protuberances of two cohering valves correspond to each other It looks as if the cell-division has stopped too early, when only the division of the I^^^^^^$5< contents and the development of the foramen has begun In some cells I found very short and curved awns in stead of the protuberances, thus showing the reduction in a somewhat less degree I have no real explanation of the phenomenon Perhaps it shows that the cell-division has been fulfilled takes place very rapidly, or perhaps a state of hunger, or perhaps it Chaetoceras with Bail, ahorted awns 500 t m Fig boréale designates has something to with micro- it it occurred in the some samples in which microspore formation in Ch decipiens was observed (but no microspores spore formation, as were found 1907, pi in Ch boréale!) Ill, fig Ch criophihim, Okamura 36) has figured the but has no remarks on explanation of the figures the says another chain many (Bot Magaz., same phenomenon it (p 105): in the text, "One Tokyo, XXI, in a chain of while in the of the cells of times divided" Also G Karsten (Valdivia-Exp., Phytoplankton des antarkt MeeXLIII 21 274 H Ostenfeld has found Ch criophihim in the res, 1905, p 118, PI 15, figs d, e) He antarctic ocean with aborted awns abnormal aspect occur the phenomenon in connected hereto: is tells that the chains of this — 80 m and supposes that „Darin ist eine Minderung depths of 100 Diese Zellen resp Zellreihen Formwiderstandes gegeben " But schweben dementsprechend in tieferen Wasserschichten; hold case where the abnormal not good in our does explanation this des , chains occur in the surface layers of the water D 11 strib i known from all distributed species of Oceanic character, northen Oceans Chaetoceras decipiens Cleve, Bib K Svenska Vet Akad Handl., Bd I, No 13, 1873, p 11, pi 1, fig 5; Gran, Norske NordhavsExp., Protophyta 1897, p 13, pi 1, figs 2—3, pi fig 34; Fauna Arctica, HI, Heft 3, 1904, p 535, pi 17, figs 1—6; Nord Plankton XIX, 24 p 74, fig 88 one of the most common species in the area It was rather rare in the pack-ice both in 1906 and in 1908, but dominant in both years in the whole series of samples from the coastal water (July— August) and in 1908 in Danmarks Havn At the last As named C boréale place it was also observed in October 1906, some of the fru- empty, and in July— September 1907, but not in larger seems thus as if the species has its real place of thriving in our area in the coastal water between the coast and the pack-ice In a number of samples, especially in the samples from July 1908 stules being quantities It the terminal awns had the peculiar Lorenzianum Grun.; and also for structure which in the coarser is characteristic awns from the but more other cells of the chains the structure was discernible, difficult to see In other respects the specimens were quite typical, awns being coherent at a part of their length, the terminal awns making the curvature at their proximal ends and then slightly e g the divergent or nearly parallel It is then not possible to refer our Lorenzianum Grun., nor to the arctic species C mitra (Ehrbg.) Cleve More probably a closer examination of the coarser decipiens from other regions will result in finding specimens of the same structure of the awns specimens to Besides this observation, another matter of found some interest was : two samples from August 1906 and in two from July 1908 have found microspore formation in the cells All these samples I have been taken in the ice-filled coastal water north of 77° N Lat the temperature of the water being between -^ 0,5° and 1,4° The examination of this microspore development does not give much In Marine Plankton from the East-Greenland Sea 275 new, as we have the excellent description and drawings of this I have only to refer the reader to this paper and to Gran's paper of 1902 (Rep Norweg Mar Fish Investig., vol.2, No 5) in which the microspore formation in Rhizosolenia styliformis was described and where considerations on the microspore problem in general were put down Similar considerations embrazing all the known cases of microspore formation^ are given by G Karsten (Valdivia-Exp., Phytoplankton d Atlant Gran processus in Chæt decipiens by (1904) Meeres, 1908) The annexed figures (Fig development of the micro- show 9) the different stages the in spores; they correspond rather closely to Gran's figures (1904) In the drawing we left chain the end is normal a contains while have find a which rest and cell of cell in one nucleus, two other cells but the the division of fulfilled the nucleus into two daughter nuclei It might be supposed that this stage could illustrate the beginning of an ordinary cell-division as well as Fig the Chaetoceras decipiens CI Cells in microspore-formation 250 t m 1) beginning of the microspore formation, but this be clear will (1904); this if is not right as there we compare this is which by Gran a great dilTerence drawing with the fig author gives here the corresponding stage of an ordinary and drawing shows that contemporaneously with in the plasma appears as the first beginning of the future foramen between two cells This fissure does not exist in my case, whereby it is proved that we have here cell-division, his the division of the nucleus a fissure the first stage of microspore formation The other figures show stages with 2, 4, and 16 daughter corresponding rather well to the figures by Gran, but his material has been better stained than mine Perhaps we have herein the explanation of the following difference, viz.: that the division nuclei of the nuclei in my material goes on a good time before the divi- sion of the plasma, thus nuclei, but only With regard terial does to not e g in the figure to the right (7— )8 plasma-lumps each we have containing the further fate of the microspores preserved allow siderations set forth 16 nuclei ma- and to the theoretical conby Gran, Bergon and Karsten I have nothing observations, 21* — 276 to add H OSTENKELl) Only one new case of microspore formation has been dis- Karsten's paper, viz the microspore formation in Chœt Lorenziamim Grun found by J Schiller (Ber, Deutsch Bot Ges., XXVII, 1909, p 352) in the Gulf of Triest The formation described corresponds rather well to the manner of sporulation found by Gran in Chœt decipiens and by George Murray (Proc Roy Soc Edinburgh, XXI, 1896, p 207) in Chœt boréale; as to the hypothesis advanced by the author on the cause of the rarity of microspores viz that the microspore formation in most species should take I have only to say place by the germination of the resting cysts that it is a purely theoretical supposition, for which we have no basis as long as we not know a single case of germination of a resting spore It is a very remarkable fact that in spite of the numerous studies on the plankton diatoms during the last two decennia, nothing has been discovered with regard to this important matIt is to be hoped that we may soon get this mystery solved ter covered since — : , Oceanic species of a northern character, a dominant species I) i strib over wide areas of the North Atlantic and its tributaries 25 Chætoceras diadema (Ehrbg.) Gran, Norske Nordhavs Exp., 16— 18; Nord Plankton XIX, p 84; groenlandicum Cleve, Bih K Svenska Vet Akad Handl., Bd 22, afd 2, No 4, 1896, p 7, pi 2, figs 3—5; Syndendrium diadema Ehrbg Prolophyta, 1897, Mikrogeologie, p 20, pi 2, figs pi 35, A, XVIII, 13 Found sparingly in one sample (Aug 1906) in the pack-ice, rather sparingly in some samples from the coastal water (July 1908) and not uncommon in samples from Danmarks Havn in August September 1907 and here with resting spores Distrib 26 Northern neritic species of wide distribution Chætoceras Wighami Brightw., Quart Journ Science, IV, 1856, p 108, pi figs 7, Microsc 19—36; Gran, Nord Plankton, XIX, 1905, p 88; Ostenfeld, Wiss Ergebn Aralsee-Exp., Lief VIII, St Petersburg, 1908, p 153, pi 5, figs 12; C bottnicum Cleve in Aurivillius, — Bih K Svenska Vet Akad Handl., Bd 21, afd Found rather sparingly in Aug.— Septm 4, No 8, 1907 in 1896, p 14, pi Danmarks Havn; water in July 1908 and here in a few samples; further single chains found in a sample rather often occurring in the coastal common from the pack-ice (July 1908) Distrib Euryhaline neritic species, known from the coasts of Euroije and Arctic countries, further from the Caspian and Aral Seas 27 Chætoceras debile Bd 20, afd.3 No 2, Cleve, Bih K Svenska Vet Akad Handl., 1894, p 13, pi 1, fig 2; Østrup, Medd oni Grøn- Marine Plankton from the East-Greenland Sea land, XVIII, 1895, p tophyta, 1897, p 23, 456, pi 277 89; Gran, Norske Nordhavs Exp., Pro14—15; Nord Plankton XIX, 1905, p 92 7, fig pi 2, figs only found in three samples from DanAug — Septm 1907, and, in a dwarfy state, in two samples from the pack-ice in July 1908 Rare in the collection, marks Havn in Di strib Northern neritic species, known from the coasts of Europe and Arctic countries, furtlier from Japan ChætocerasfurcellatumBail., American Journ of sc & arts, ser 2, vol 22, 1856, pi 1, fig 4; Cleve u Grunow, K Svenska Vet Akad Handl., Bd 17, No 2, 1880, p 120, pi 7, figs 136—137; Gran, Bibliotheca Botanica, Heft 42, 1897, p 7, pi 1, figs 15—16; Nord Plankton, XIX, 1905, p 95 28 Occurs as one of the characterizing species in a group of samfrom the inner part of the pack-ice, in July 1908 Further some Chœtoceras-chains in samples from Danmarks Havn in 1907 and in the coastal water in 1908 may perhaps be referred to this species, ples but the determination is not sure Di strib Arctic neritic species, known from the Arctic Seas, along the Norwegian coast as far southwards as Cape Stadt Chaetoceras sociale Lauder, Transact Microsc Soc, vol 12, 8, fig 1; Cleve, Bih K Svenska Vet Akad Handl., afd.3 No 4, 18%, p 9, pi 2, fig 9; Gran, Nord Plankton XIX, 29 N reacliing 1864, p 77, pi S., Bd 22, 1905, p 96, fig 123 Occurs in great quantities in samples from Danmarks Havn Aug.— Septm 1907, and with resting spores Further common some samples from the coastal water in July 1908 and rare others also here mostly with resting spores in in in ; D i strib Northern neritic species known from the coasts of Europe, and Hongkong Iceland, Arctic countries Chaetoceras gracile Schutt, Ber Deutsch, bot Ges., 1895, p 42, 13; vix Paulsen, Medd Komm Havundersøg., Plankton I, 1905 København, p 5, figs — 7; non Apstein, Wiss Meeresun30 pi 5, fig 3, ters,, Abt Kiel, N F., Bd 11, 1909, Bih pi 2, fig p 135, fig ; septentrionale Cleve, Svenska Vet Akad Handl., Bd 22, afd 3, No 8; vix Østrup, Medd Grønland, XVIII, 1895, fig 4, 1896, p 9, p 457, pi 7, 88 two samples from Danmarks Havn, August 1907, and in one sample from the coast water, July 1908, I found a small solitary Chcetoceras with resting spores As my figures (Fig 10) show, it must be identified with Cleve's C septentrionale from Baffin Baj', but hardly with Østrup's original species of that name On the In 278 other hand is it H probable that Ostenfeld gracile Schutt is the same species, we compare Schütt's figures of cells with chromatophores with my fig 10, we will find a close resemblance; on the because if contrary his figures of resting spores differ from mine, but he has not drawn these spores in situ within cells, and it is perhaps permitted to doubt, if they belong to the species in question Paulsen (1 c.) has given figures from Østrup's original material and considers his form as identical with Schütt's gracile, but I Chœtoceras gracile Fig 10 doubt if he right is in doing so Schutt 500 t The question m is a much intri- cate one The note by Apstein about these small solitary species drawings of a species from the Baltic the locality of Schütt's species which the author names C gracile but, I think, hardly correct; I myself know Apstein's form from the Belt Sea (Baltic) and have found it with resting spores which differ considerably from those of C gracile; they have two rather large spines on the primary spore-valve (in the same manner as the spores of C latest — contains — debile) and often The also small spines, while the secondary valve is has only one chromatophore, as also drawn by Apstein, and the corners of the cell in side view are not contracted; all these distinctive marks separate it from the true C gracile, and I propose to name it C ceratosporiim nov sp.; it is only known from the Baltic, where it occurs in the spring and seems to have its true home in the inner part, as I have seen it in samples kindly sent me by Dr K M Levander of Helsingfors Anj'how the small solitary Chœtoceras species require a revision, smooth correctly species —— Marine Plankton from the East Greenland Sea holm, Bd D i No 2, Lemmermann given by as the treatement 2, 1904) is (Arkiv f 279 Botanik, Stock- not a good one strib, (of Ch gracile, sens, lat.): Euryhaline neritic species known from coasts of Greenland and Europe Biddulphia Gray, 1831 31 Biddulphia arctica (Brigtw.) Boyer, Proc Acad, of Nat Sc, Philadelphia, 1900, p 714; Gran, Nord Plankton, XIX, 1905, p 109, fig 143; B.balœna Brightw., Quart Journ Microsc Sc, vol.8, 1859, p 181, pi 9, fig 15; Triceiatium arciiciim Brightw, ibid, vol 1853, 1, p 250, pi 4, fig 11 Found sparingly in three samples from Danmarks Havn, Aug Septm 1907 D ist rib form Littoral (not true plankton form) B from the Arctic coasts Pennatæ Fragilaria Lyngb., 1819 Fragilaria islandica Grun in V Heurck, Synopsis, 1883, 37 Jørgensen, Bergens Museums Skrifter 1905, p 102, pi 6, Nord Plankton XIX, 1905, p 114, fig 153 Gran 10; 32 pi 45, fig fig ; Only found in Danmarks Havn, where plankton, although only scattered, in all it was present three years July in the — October Distrib Arctic neritic species, known from the coasts of the Arctic sea; probably not a real plankton form European Fragilaria oceanica Cleve, Bih K Svenska Vet Akad Handl., Bd 1, No 13, 1873, p 22, pi 4, fig 25; Grunow, Dial v Franz Josefs Land 1884, p 55, pi 2, fig 14; Gran, Bibliotheca Botanica, Heft 42, 33 1897, p 20, pi 1, figs 6—9; Nord Plankton XIX, 1905, p 114, figs 154-155 In 1906 only very ỵeyv samples contained this species, and only few specimens, while in 1907 and 1908 it was a dominant feature in July and August samples from Danmarks Havn and the coastal in In the pack-ice it was not at home, recorded in few specimens from three samples (two in 1906 and one in 1907) July water October Several of the forms distinguished by Gran (1905) according to the curvature and twisting of the chains, were seen from 1907 and 1908 resting spores In all were present, often samples in large quantities Arctic neritic species known from Arctic Sea and a little more southwards Distrib Euopean Davis Strait and the 280 H Ostenfeld Fragilaria cylindrus Grunow, Diat v Franz Josefs Land, 1884, p 55, pi 2, fig 13; Gran, Bibliotheca Botanica, Heft 42, 1897, p 20, pi 1, figs 4— 5; Nord Plankton, XIX, 1905, p 115; Jørgensen, Bergens Museums Skrifter, 1905, p 102, pi 6, fig 34 This species resembles the foregoing one very much, and only possible to distinguish them Hence when it is the ignified frustules are seen in may be that some of the records of F oceanica I have seen sure specimens only in one sample from Danmarks Havn, July 1908 valvar view it include this species of which Di strib Arctic neritic species of atiout the foregoing, but often overseen Thalassiothrix Cieve 35 et No 17, 2, distribution as the Grun., 1880 Thalassiothrix longissima Cleve Akad Handl., Bd same 1880, p 108; unters., Abt Kiel, N F., Bd 4, 1899, p 28, Grun., K Svenska Vet et G Karsten, Wiss Meeres- 11; Gran, Nord PlankXIX, 1905, p 116; Synedra thalassiothrix Cleve, Bih K Svenska Vet Akad Handl., Bd 1, No 13, 1873, p 22, pi 4, fig 24 fig ton, Only a single specimen found in a sample from the pack-ice in Aug 1906 D e g i in strib Northern oceanic species, often occurring in great quantities, Denmark Strait and Irminger Sea Achiiaiithes Bory, 1822 36 Vet Achnanthes tæniata Grun Akad Handl., Bd 17, No 2, bliotheca Botanica, Heft 42, 1897, XIX, 1905, p 122, fig p 105, pi 8, fig in Cleve 1880, p 22, et Grunow, pi 1, fig p 9, pi fig 10; 165; Jørgensen, Bergens K Svenska 5; Gran, Bi- Nord Plankton, Museums Skrifter, 1905, 27 As Gran (1905, c, in nota) has pointed out, Grunow's and Jørgensen's figures represent chains with resting spores, while in Gran's two quoted papers we find the normal vegetative chains Found in three samples from Danmarks Havn (Aug 1907 and July 1908) and, with resting spores, in one sample from the packice (July 1908) Perhaps overseen in other samples, as it resembles Fragilaria oceanica and Naviciila septentrionalis very D ist rib inner Baltic Arctic neritic species known from much the Arctic Sea and the (in spring) Navicula Bory, 1826 37 Navicula septentrionalis (Grun.) Gran, Bibliotheca Botanica, 1897, Heft 42, p 9; Nord Plankton, roneis septentrionalis XIX, 1905, p 124, fig 167; StauGrunow, Diat v Franz Josefs Land, 1884, p 105, Marine Plankton from the East-Greenland Sea pi 1, fig p fig 48; Jørgensen, Bergens 24; Libellus 439, pi 8, (•?) Museums septentrionalis Østrup, 281 Skrifter, 1905, p 106, pi 7, Medd om Grønland, 1895, 97 fig some samples from Danmarks Havn and the coastal water, in 1906 1908, but scattered, and perhaps, as said under Achnanthes, sometimes not distinguished from the other band-like Found in — species D strib i known from Arctic neritic species, Sea the coasts of Greenland, from Barent and from Murman 38 1897, p Navicula Vanhöffenii Gran, Bibliotheca Botanica, Heft 42, 1—3; Nord Plankton, XIX, 1905, p 124; Jørgensen, 9, pi 1, figs Bergens Museums Skrifter, 1905, p 105, pi 7, fig 22; N septentrionalis Cleve, Bih K Svenska Vet Akad Handl., Bd 22, afd 3, No 4, 1896, p 11, non Grunow Østrup, Recorded from four samples from Danmarks Havn (Aug and perhaps overseen — Septm D Greenhmd 1907, July 1908), but rare, and strib i arctic known from Arctic neritic species, Norway, from Barent and Murman the coast of Seas, further from the inner Baltic (in spring) Amphiprora Ehrbg., 39 1843 Amphiprora hyperborea(Grun.) Gran, 1897, p 10; Fauna Arctica, HI, 3, Bibl Botanica, Heft 42, 1904, p 543, pi 17, fig 14; Nord Plankton, XIX, 1905, p 127; A paludosa, var.? hyperborea Grun in Cleve et Grunow, K Svenska Vet Akad Handl., Bd 17, No 2, 1880, p 62, pi 5, fig 86 In 1906 only found in one sample from the pack-ice and in 1907 two samples from Danmarks Havn, in 1908 found scattered over the whole area from Danmarks Havn to the outer part of the packJune — September ice; always in few specimens in D i strib Arctic neritic species know^i from Greenhind, arctic Norway, Barent and Murman Seas Nitzscliia Hassall, 1845 40 Nitzschia frigida Grun., Akad Handl., Bd 17, No botanica, Heft 42, 1897, p 2, p 10, in Cleve et 1880, p 94, pi 1, fig Grunow, K Svenska Vet Gran Bibl fig 101; pi 5, 11; Nord Plankton, XIX 1905, 129 Found 1907) and three samples from Danmarks Havn (Aug samples fiom the coastal water (Aug 1906, July scattered in in three 1908) Distrii) Arctic coast species, not true plankton form, Arctic coast and the inner Baltic known from the 282 H Ostenfeld Nitzschia seriata Cleve, Vega Exp vetensk iaktl., Bd 3, 1883, pi 38, fig 75; Gran, Nord Plankton, XIX, 1905, p 129, fig 174; fraudulenta Cleve, 15 Ann Rep Fishery Board for Scotland, part III, 1897, p 300, flg 11; Synedra Holsatiæ Hensen, Ber Komm Uniers Deutschen Meere, 1887, p 91, pi 5, fig 50 41 ^ Only found in Danmarks Havn (Aug 1907, July 1908) in four samples, but mostly rare Di strib Widely distritjuted in open seas and along the coasts, pro- tjably a neritic species of northern, but not arctic cliaracter 42 1897, p Nitzschia delicatissima Cleve, A Treatise of Phytoplankton, 24, pi 2, fig 22; Gran, Nord Plankton, XIX, 1905, p 130 Found together with the preceding species in two samples from Danmarks Havn, Aug 1907 D ist rib Mucli like the preceding, but more restricted Nitzschiella Rabenh., 1864 43 Nitzschiella closterium (Ehrbg.) Rabenh., 1864, p 163 ; pi 4, fig 7; p 42, pi 15, Fl Europ Algar., Ceratoneis closterium Ehrbg., Kreidethierchen, 1840, p 64, W Smith, Syn British Diatoms I, 120; Gran, Nord Plankton, XIX, 1905, p 129, fig 172 Nitzschia closterium fig I, Found together with the preceding in two samples from Danmarks Havn (Aug 1907) and further in one sample from the coastal water (July 1908); a littoral species which sometimes occurs in plankton as Distrib it often inhabits mucilage of other organisms Ubiquitous along the coasts Flagellatæ II Chrysomonadineæ A Dinobryon Ehrbg., Dinobryon pellucidum Levander, Acta Fenn., 12, No Dinobryon pi 1838 b 18, figs 2, 1894, p 31, pi 2, Lemmermann, 9— 10; fig Soc Fauna & Flora Dinodendron balticum SchuU; ; Deutsch, bot Ges., Ber Nord Plankton, XXI, p 4, figs 1900, p 514, 13-14 Single specimens occurred in a sample from Danmarks Havn in 1906, but besides that the species was distributed in the outer parts of the pack-ice, east of ca 12° common, When especially in 1908 W (in Long., in some samples it the temperature rose above 7° and the salinity over 34 disappeared was 1906 found only in two samples) "^/oo it — August July strib A boreal neritic species, known from the coastal waters of Greenland, Iceland, Spitsbergen, Norway, Færoes and the Baltic D i Phæocystis Lagerheim, 1893 Phỉocystis Pouchetii p 32; Ưfv feld, Arch Sv Vet Akad f (Hariot) Lagerh., Botan Notiser, 1893, Forhandl., 1896, Protistenkunde, III, p 277, figs 1904, p 295, 1-5; Osten- fig Found scattered over the area, in two samples of 1908 rather common, but not in great quantities, probably because the season has been too late Not seen in the samples taken in Danmarks Havn, but only recorded from the coastal water and the pack-ice July— August D strib A i boreal-arctic neritic species ous part in the plankton, off northern Norwav, etc B f i in Davis and which Denmark often plays a conspicuaround Iceland, Straits, Coccolithophoridæ Coccolitliophora Lohmann, 1902 Coccolithophora pelagica Wallich) Lohmann, Arch f Protistenkunde, I, 1902, p 138; Coccosphœra p Wallich, Ann Mag Nat ( 284 1877, p 348, pi 17 Hist., London, ; Ser B, 1898, vol H OSTENKELD Murray and Blackman, Trans Roy Soc, 190, p 439, pi 16, figs 6—10; C atlantica Ostenfeld, Zool Anzeiger, 22, 1899, p 436, fig was rather surprising to find a Coccolithophora in the plankton from such high latitudes and in such arctic water It was seen in 1905 in three samples from outside the pack-ice and in 1908 in three samples also outside the pack-ice, but a little more southwards; in two of the latter ones it w^as rather common, especially in lumps It did not occur in any of the samples west of 11° of mucilage Is W Long On closer examination it appeared that all the specimens examined were dead, as no nucleus nor chromatophores, Disrib A temperate oceanic organism, very in the Atlantic Pontosphæra borealis ^22 : coccolithi elliptici, similes: flagella nucleus adest In et 3— A fi 1902 longi, plani vel leviter concavi, in spec, preservatis non 17— onmes distincti; Fig 11 seven samples (three from 1908 and four from 1906) from 'O' ifi: ^% V I / and outside (i e not W of 11^ W I lithophora present Pontosphæra borealis n sp 8ÜÜ t m 11 it found an interesting organism, viz.: a species of the genus Pontosphæra As mentioned above the occurrence of Coccolithophoridœ in arctic water was a new thing, but the Cocco- Long.) Fig common nov sp Cellulœ solitariœ globosœ, chromatophori the outer part of the pack-ice 1'^^^ distributed and Ocean Pontosphæra Lohmann, were etc., July —August present ^er was dead It is another mat- with the Pontosphæra, as its plasma showed cells most probably w^ere living when that the caught It is then the living in arctic water first The record of a species of Coccolithophoridœ species found must be referred to the understood by H Lohmann, but I can genus Pontophœra, as it is not identify it with the species hitherto described (Lohmann, p 129—332) The cells are mostly globose, rarely of a more oblong , form, the coccoliths are plane or slightly concave, all of the same shape, elliptic and lying closely together, covering the whole surface cell As only preserved material was examined no flagella were found, and it was not possible to discover chromatophores^ whereas a nucleus was seen By using acids the coccoliths disap- of the peared immediately The new distinct species resembles P inermis Lohm., naked pole ("Geisselpol") for the flagella but has not the July — August Marine Flankton from the East-Greenland Sea In but most of the samples it 285 occurred together with Cocx pelagica, did not occur in greater quantities, perhaps because it small that it is so only in a small part caught by the nets is it Silicoflagellatỉ C Distephamis Stưhr, 1880 Distephanus speculum (Ehrbg.) Haeckel, Challenger Radiolaria, 1889, p 263, pi XI, p figs.; 1560; Lemmermann, Nord Plankton, XXI, Most of the specimens found to var septenarius (Ehbg.) Jørg., Found scattered over Danmarks Havn, in 1908 three samples f the area; also in in must be the samples 1907 Lemm., in three c, referred fig 104 samples from and in 1906 in As the specimens the coastal water, the outer part of the pack-ice in 103— 104 p 31, figs regularis in Rep., Ber Deutsch, bot Ges., 1901, examined had plasma, they must have been living when caught D strib, (of the form) Ivarajaktjord in West-Greenland, Baltic; (of the i species) oceanic species of worldwide occurrence, but hardly arctic Appendix: Pterospermataceæ Pterosperiua Pouchet, 1894 Pterosperma Vanhöffenii (Jørg.) Ostenfeld, Vidensk Medd København 1901, p 151; Pterosphœra V Jørgensen; Pterocystis V Lohmann, Eier u sogen Cysten der Plankton-Expedition, Naturh For., 1904, p 44, pl 7, flg 10 Single specimens near the coast (in D i strib Atlantic 28 )1 in several samples in the (10) in 1908, both outer part of the some of the specimens were empty July — August A temperate oceanic organism, known especially from the pack-ice At least North found Danmarks Havn) and ... Danmark-Expedition 1906—1908: I List of Diatoms and Flagellates by H Ostenfeld II Protozoa by H Ostenfeld III Peridinales by Ove Paulsen IV General remarks on the Microplankton by H Ostenfeld and Ove Paulsen... OF 73° 30' N LAT.) COLLECTED DURING THE "DANMARK EXPEDITION'^ I LIST OF DIATOMS 1906-1908 AND FLAGELLATES BY C H OSTENFELD 1910 XLIII 20 INTRODUCTION During the outward and homeward voyages of... summarily The exa- The littoral diatoms and the diatoms of the ice-floes are determined by Mr E ØSTRUP who publishes his results together with a treatment of the freshwater diatoms Marine Plankton