Memoirs MCZ 1001

a JUN 1927 Icmoirs of i\n ||lus£um of Comparatibc ^ooloc];n AT HARVARD COLLEGE Vol X No REPOETS ON THE RESULTS OF DREDGING, UNDER THE SUPEETISION OP ALEXANDER AGASSIZ, IN THE GULF OF MEXICO (1877-78), IN THE CARIBBEAN SEA (1878-79), AND ALONG THE ATLANTIC COAST OF THE UNITED STATES (1880), U S COAST SURVEY STEAMER "BLAKE," LlEUT.-COM C D SiGSBEE, U S N., AND CoMMANDER XXIV Report on (Publislieil the P Patterson ami J E WITH THIRTY-TWO PLATES CAMBRIDGE: for tlje JHuseum September, 1883 Agassiz Hilgard, Superintendents U S Coast and Geodetic Survey.) PrmtelJ COMMANDING I By Alexander Echini by permission of Carlile Part R BaRTLETT, U S N., J INTEODUCTION the Echini The Preliminary Reports on of the BUike Expeditions for 1877-78, for 1878-79, and for the summer of 1880, were published in Vol v No Report will and Vol VIIL, No M C Z., be foimd all 9, Bull Straits of Florida C Z In the former the Stations occupied in the Gulf of Mexico and explored along the West India in the latter, the Stations : M 2, Bull Islands and the Atlantic coast of the United States therefore, only principal localities in sufficient give in this Report, I number to indicate the geo- graphical range and bathymetrical distribution of each species as determined by the dredgings of the " Blake." Challenger Expedition I graphical distribution of species collected In the Report on the Echini of the have given a of the bathymetrical and geo- list the species of Echini then known, including the all by the Blake Expeditions The Preliminary Reports on the Deep-sea Echini, collected by Mr Pourtales published in the Bull M C Z., porated in Part Coast Echini," II 111 Vol I., No off the Florida Reefs, The final Report was incor- of the Revision of the Echini under the Cat The importance of M C Z., No VII Mem M were name C Z., Vol III., of " East 1872-74 the collection of the Echini brought together during the cruises of the " Blake " is well shown by a comparative statement of our knowledge of the Caribbean Echinid Fauna before and after the explorations undertaken under the auspices of the United States Coast Survey There are now known eighty-three species bean Fauna Of Pourtales in the these, eleven were "Bibb" and " for the first time in the from the Carib- added by the dredgings of Count Hassler," nineteen were discovered by the " Blake," and thirteen species previously dredged of Sea-urchins known from other districts were Caribbean and adjoining seas by the Coast INTRODUCTION iv Survey Expeditions, so that the list of species has been more than doubled by the dredgings made since 1876 In consequence of the great delay in ^ireparing the illustrations of the structure of the Salenidas, the Echinothurife, and more minute less well known many of the Spatangoids, the concluding Part of this Report will appear on their completion The details of the geographical distribution of the Echini of the having already been given in the Preliminary Pieports No D, 1878, Vol VIII No 2, occupied by the " " C Z., Vol V 1880), to avoid repetitions I merely refer to the previously published records, as well as to the tions M (Bull Blake '• Bkke " (Bull M list dredging of the sta- C Z., Vol VI No 1, 1879, Vol VIII No 4, 1881) These give the position, the depth, the temperature, and the character of bottom ent specialists, tlie who have On the completion of the Reports by the kindly consented to work up differ- collections of the tlic " Blake," including the examination of the Ijottom samples, I hope to make a revision of the geographical and Ijathymetrical distribution of the various groups, so as to give a good picture of the animal cijjal localities regions associated at the prin- i which make up the Fauna characteristic of certain well-defined Nothing can be moi-e different, than the animals for instance, found associated on the rocky bottom along the southern slope water) of the Florida Reef, on the Pourtales Plateau, with Corals, Rhizocrini, and of ooze of the trough of &c.) ; tlie Starfishes, Ciulf from those found its in (in predominance the calcareous Stream (Lamellibranchiates, Holothurians, and again from the association of the masses of Gorgoniae, and Terebratula^ the trawl off the north coast of Nor can there be deep Cuba, brought up a greater contrast in a single Salenite, haul of l)etween the inhabitants of the Pteropod ooze in deep water ofF the west end of Santa Cruz, witli its preponderance of Phormosomaa, of Asthenosoma^, and Ilyalonemae, and those of the forests of Pentacrini and Gorgonise, and the accompanying ComatuljB and Ophiurans, living in such abundance on the windward coast of St Vincent We may contrast, again, the deep-water coral ooze, mainly made up Fauna off of a most remarkable the Tortugas, in the association of Fishes INTRODUCTION !ind V Crustacea, with the hauls in deep water, at special localities, made up entirely of thousands of specimens of single species, either of Ophiurans, of Echini, of Comatula^, of Crustaceans, or of Gorgonia^ Take again the bottom along the rid perhaps the most interesting of the recent Cidarida3 is known have not shown any great or striking radioles With the exception of some of the far the living Cidaridtc variety in the form of the recent species of the genus Gonioddaris, the radioles as a whole are characterized by their great uniformity, while great variation in the shape and and Ci'etaceous species the recent Cidaridae, it is size among the fossils of the fixmily the of the radioles of some of the Jurassic most remarkable In the description of species of has not been unusual to lay great stress upon the differences noticed in the shape and ornamentation of the radioles parative studies of recent and fossil Com- types have shown the practice to be dangerous, and the discovery of D Blakii plainly pi'oves that hereafter must proceed most cautiously in the determination of species from the char- acters of the radioles alone, no matter differ Certainly, if how strikingly they may appear to the present species had been dredged without three huge fan-shaped spines, it we its would have been unliesitatingly placed genus Dorocidaris, and been perhaps referred even to Z) pitpilhta, two or in the although there are differences in the coronal plates of the test and in the abactinal PLATE XXV Agassizia excentrica A Ao Fig Seen 20 in profile, covered with spines, A specimen of the same size, actinal side The same, seen from the aljactinal side .same, seen facing the odd anterior ambulacrum The same, seen facing the anal system Young Agassizia, The same, mm .seen facing The same, from the long cHameter seen in profile, denuded The same, seen from the The mm (posterior extremity) long, diameter, seen in profile the anal system abactinal pole The same, seen from the actinal side Enlarged abactinal system, with adjacent part of test of a small specimen 6.5 mm long diameter Abactinal system of a young Aga.ssizia, mm long, diameter Actinal system of same Magnified miliary spines of the lateral One of the large ambulacral suckers of the odd anterior petaloid a specimen 11 Fig 16 fascicle mm long, diameter Four ambulacral suckers from same, somewhat ambulacrum, expanded, from contracted of the outer petaloid part of the odd anterior ambulacrum, "Blake"£chini Plffi' ^«?5'kh^ A=^ ^^^ ^^m^ "''.'^rc/>"''^' ,!' ^ p"5o k its ? ^; ^ ^ >.''h ^ i\ -,>-;-> -Sr;' '-'j^i% AAj&Koer * w J » ** PLATE XXVr UrechinuB naresianus A Aa 1-3 Actinostome of specimen 33 mm long, diameter Fig Fig Abactinal system and adjoining part of test of same Fig Anal system and adjoining part Rhinobri33U3 micrasteroides A Aa Fi" Specimen 32 mm of test of same long, diameter, seen 5, from the abactinal Schizaster (Periaster) limicola A Aq mm Fig Anal system of specimen Fig Apical system, witli surrounding part of (i8 7-13 Fig long, diameter test of side, natural size profile Enlarged view of posterior extremity of subanal same Brissopsis lyrifera Agass Elongated type, seen from the abactinal The same, seen in side test, showing the anal system and fasciole, fasciole Portion of lateral interamlnilacral part of test near the ambitus Portion of posterior lateral ambulacral zone Portion of anterior lateral amljulacral zone Globular type of the species, seen from the abactinal pole, natural The same, seen size in profile Posterior part of test of same, enlarged, corresponding to Fig in the elongated type Corresponds to Fig 10 of the elongated type Corresponds to Fig 11 of the elongated type Corresponds to Fig 12 of the elongated type with the "Blake" Echini PI XW! ^jyi^ssa^,^ '^ U) s ^^^i?#'' "fa :>*'"; '* 'jji -v^ -f ;' J ,»» 6W A.Ag' del.Roettei- I.Lh Pr;iiled bvAMcisei PLATE XXVII Macropneustes spatangoides A Aq Fig Seen in Fig Another specimen, seen from the abaotinal Fig Enlarged view of actinostome of same profile, natural size side, natural size Fig Enlarged view of the reticular peripetaloiis fascicle of the specimen of Fig Fig Enlarged view of anal system and subanal fasciule of the same Fig Profile outline of a large specimen, with high posterior extremity, natural size Fig The same, seen from atrophied, as is tlie abactinal pole ; the apical part of the petaloid ambulacra has become so frequently the case in allied genera "Blake" Echini PI mi Printed byA-Meisel Fig "Blake" Echini