CRLSSI o SMITHSONIAN INSTITUTION UNITED STATES NATIONAL MUSEUM Bulletin 74 ON SOME WEST INDIAN ECHINOIDS BY THEODOR MORTENSEN Of the Zoological Museum, University of Copenhagen eee eles, WASHINGTON GOVERNMENT PRINTING OFFICE 1910 BULLETIN OF THE UNITED STATES NATIONAL MUSEUM IssuED OctosER 3, 1910. ADVERTISEMENT. The scientific publications of the United States National Museum consist of two series, the Proceedings and the Bulletins. The Proceedings, the first volume of which was issued in 1878, are intended pri- marily as a medium for the publication of original, and usually brief, papers based on the collections of the National Museum, presenting newly-acquired facts in zoology, geology, and anthropology, including descriptions of new forms of animals, and revisions of limited groups. One or two volumes are issued annually and dis- tributed to libraries and scientific organizations. A limited number of copies of each paper, in pamphlet form, is distributed to specialists and others interested in the different subjects as soon as printed. The date of publication is printed on each paper, and these dates are also recorded in the table of contents of the volumes. The Bulletins, the first of which was issued in 1875, consist of a series of separate publications comprising chiefly monographs of large zoological groups and other general systematic treatises (occasionally in several volumes), faunal works, reports of expeditions, and catalogues of type-specimens, special collections, etc. The majority of the volumes are octavos, but a quarto size has been adopted in a few instances in which large plates were regarded as indispensable. Since 1902 a series of octavo volumes containing papers relating to the botan- ical collections of the Museum, and known as the Contributions from the National Herbarium, has been published as bulletins. The present work forms No. 74 of the Bulletin series. Ricuarp RATHBUN, Assistant Secretary, Smithsonian Institution, In charge of the United States National Museum. Wasuineton, D. C., September 7, 1910. III : TABLE OF CONTENTS. Tmitroduchionsaa sats cree Sacer ee eee Se Saks ada ciate crete mote a elton nye yoier eee ee Descriptionjolspeciesi a4 Sat aa heey Cases eal. Nae ape sialS = sere ee ee nae ee eee ee eT Walocidamigumi cams) (Monte sen)) marae ar ele eater rape eee e fa ee eS ae oe tee see ap Tretocidanisibartletit (Ac AGASSIZ) — te rope octet Sanpete ee oes dees See eee ee oe eee le Stylocidanisilinesta mew: SpecCles = .2e sean e 2 ais eee ais laps ee ne ei ee eee te ae C@idaristabyssicolasvan. teretispina, mew. Varletyo. +2202 se esses. sy eo ee eo eee eee Cidarisingosa) (Et. Ws' Clark) ooo = acne = «2 ose ee FAS Sesto a eh slays eres ee se eee s Areeosoman belli Mortensen =: <9! 4 sj... 212y=;-f=)-\ohaehe ea eStart = eta cee Seis ke ee cee beatae Diademaranittllarum emp pie). payee tates el asta ree a els Aya e oeeeeee ee ee acter Revised list of the Echinoids known to occur in the American region of the North Atlantic, and Wun ea West iLO CS ee eaten eres acters ae ee Se deh Sega ceet ee eS See ee Hxplanationrotplatesi ssc =-. seston eee oe et EE eee Bs SS eee SS Se Ce Pe Index 22 26 29 ON SOME WEST INDIAN ECHINOIDS. By Turopor MORTENSEN, Of the Zoological Museum, University of Copenhagen. INTRODUCTION. In my work on the Echinoidea of the Danish Ingolf expedition preliminary diag- noses are given of several new species of echinoids. These diagnoses, though, I think, in general sufficient for the recognition of the species, are, of course, by no means detailed, and I hope in the future to be able to publish full descriptions of all the species which I have thus established. The difficulty is that most of these are not represented in the Copenhagen Museum, so that I must depend on what oppor- tunities there may be for me to get material from other institutions. Such an opportunity was accorded me on a visit to the U. S. National Museum in the spring of 1906. I found there a good representation of two of my previously indicated species, namely, Calocidaris micans and Arzosoma belli. I was allowed to examine this material in detail, and as I had no time to do it during my short stay in Washington, I was permitted to borrow the specimens and to have them sent to Copenhagen, where I could study them exhaustively. Together with this material I also received some other specimens of West Indian cidarids. The study of these specimens, together with some collections made by myself during a stay in the Danish West Indies in the winter 1905-6, made it clear to me that still another species of cidarid, besides those previously known, occurs in the West Indian seas, probably hitherto confounded with Cidaris cidaris (Dorocidaris papillata), as has been the case with so many other species. A description of this new form is included here. A full description is also given of the much discussed, but hitherto not thoroughly described, Tretocidaris bartletti, of which species I have likewise had material sent forstudy. Finally a few remarks are added on the species Cidaris abyssicola and (. rugosa. The revised list of North American Atlantic and West Indian Echinoids may, I hope, prove not without value. : 2 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. DESCRIPTION OF SPECIES. CALOCIDARIS MICANS (Mortensen). Plate 1; plate 14, figs. 5-6; plate 15, figs. 1-2, 7; plate 16, figs. 3-5, 7-8, 10, 13-14; plate 17, figs. 7, 12-13. Dorocidaris (?) micans Tu. MortenseN, Ingolf Echinoidea, pt. 1, 1903, p. 23, pl. 9, fig. 26; pl. ll, fig. 24. Calocidaris micans H. L. CuarK, The Cidaride, Bull. Mus. Comp. Zodl., vol. 51, 1907, p. 211, pl. 3. Two specimens of this very beautiful cidarid were received for examination from the U. S. National Museum, and form the basis of the following description. They were dredged at Albatross stations 2348 and 2354. The very beautiful speci- men figured on plate 1 I have not examined in detail. It is the specimen mentioned by Clark as “the most beautiful echinoid’’ he has ever seen. The photograph was made at the U. S. National Museum. Measurements. | Haak Number of | | | Width of— | plates, re - | i | Dinwelerg eng | el eel ebene iicccoaenl hemes eR oe Cler: 2 ‘| tem. | tem. | Stome. Inter- | Int oles ; | 2 | Ambu- ante | Ambu- amen | | | lacra- | Tecra. | 1¢T@- | ‘lacra, di | : | } mm. mm.e@ | mm. mm | mm. | mm | mm. | 48 87 (44) | 21 | 11.5 | 20 =| 5 24 | 94-95 8-9 Broken. 28 20 (25) | 13.5 7.5 13 ot ||, 18 | 53-54 | 67 Do. aThe figures within the parentheses indicate the height from the mouth opening to the anal opening; the other figures indicate the height of the corona. The test is high, the height of the corona being from 72 to 75 per cent of the horizontal diameter; the sides are regularly curved, not flattened above or below; the edge of the peristome is not incurved; the peristome and apical system are not flattened, but rise in continuation of the curvature of the corona, which makes the whole test appear almost spherical. The ambulacra are in the two specimens 20.9 per cent and 23.1 per cent of the interambulacra in width (Clark gives 25 per cent); each ambulacral plate carries inside the primary tubercle a secondary tubercle of almost equal size in the middle of the plate (Plate 14, fig. 6); a very small tubercle is found at the lower edge of the plate between the two larger tubercles; there are thus four longitudinal series of tubercles in the interporiferous zone, except quite near the peristome and a somewhat larger part at the abactinal end, where the inner tubercle is found only on one side, irregularly alternating; at the upper end it has not appeared as yet. There is scarcely a distinct, naked median line, and Clark’s “nearly bare median ambulacral areas” is not an adequate expression for the specimens at hand; the specimen figured by Clark also appears to have distinct inner series of tubercles. The above description is based upon the larger specimen; in the smaller specimen the inner tubercle has not yet appeared on both sides, even at the ambitus, but stands irregularly alternating, now on several plates in succession on one side, then on some plates on the other side, and so on, quite irregularly. In this specimen SOME WEST INDIAN ECHINOIDS. 3 the ambulacra are thus more in accordance with Clark’s description (which is, however, made from a specimen 61 mm. in diameter); here the interporiferous zone is also a little more than half the width of the whole ambulacrum, whereas in the larger specimen it does not exceed half that width. The pores are not yoked; the partition wall is rather broad, somewhat elevated; the part of the plate above the pore pair is slightly elevated (Plate 16, fig. 14). The poriferous zone is dis- tinctly sunken in the larger specimen, less so in the smaller one; Clark’s statement, “oriferous zone scarcely at all sunken,’’ thus does not hold for the species. The number of ambulacral plates is unusually large (see above); 17-19 ambulacral plates correspond to one interambulacral plate toward the abactinal side in the larger specimen, 15-16 in the smaller specimen. The interambulacra are described by Clark as having the ‘‘median interambu- lacral area not at all sunken, covered with numerous miliaries and with more or less horizontal grooves or narrow furrows, such as occur in Temnocidaris.” The specimens before me do not agree with this. The median part of the area is dis- tinctly sunken, especially in the larger specimen; the horizontal furrows across the inner part of the plates are very distinct, especially in the larger specimen; they are quite similar to those found in Cidaris cidaris (Dorocidaris papillata), only some- what more regular (Plate 14, fig. 5, to compare with Plate 14, fig. 1, of Prouho’s Recherches surle Dorocidaris papillata). The expression, ‘‘such as occur in Tem- nocidaris,”’ is less fortunate, as there is no trace of the peculiar pits so character- istie of Temnocidaris, and it is much more natural to compare this feature in C. micans with the quite similar structure found in the more nearly related Cidaris cidaris. The areoles are not very deep; only the two lowermost are confluent, all the others being distinctly separated by a wall with tubercles, narrow below, eradually becoming broader toward the abactinal side. The tubercles surrounding the areoles are somewhat larger than those outside; the rest of the plates is covered by smaller, not very closely set, secondary tubercles. There is no distinct bare median space. The apical system is essentially as in Cidaris. In the specimen figured by Clark all the ocular plates are in contact with the anal area; in the larger specimen before me only two ocular plates are in contact with the anal area, in the smaller specimen all are widely excluded. The anal area is covered mainly by two circlets of plates, an outer, larger, and an inner, smaller, within which some quite small ones are found around the anal opening. In the smaller specimen the whole apical system, in the larger only the anal area, is considerably elevated. The genital open- ings are rather distant from the edge, small—perhaps both specimens are males. The whole apical system is rather closely tuberculated. The peristome has 16-17 ambulacral plates in each series; those of each two neighboring series do not join within, so that the interambulacral plates continue almost to the very edge of the mouth. The latter bear comparatively few tubercles, the peristome being somewhat sparsely covered with spines. In the smaller speci- men there are only 13-14 peristomial ambulacral plates in each series, and the inter- ambulacral plates do not reach the edge of the mouth. The radioles are, as described in the Jngolf Echinoidea and by Clark, very characteristic; smooth, as if polished.* They are rather fragile, almost all of them a For section, compare Jngolf Echinoidea, pt. 1, pl. 11, fig. 24. 4 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. on the specimens at hand being broken; one shows distinct traces of having been regenerated. They reach a very considerable length, more than three times the horizontal diameter of the test (Clark); they are cylindrical, scarcely tapering at all toward the point (Plate 1). Sometimes they show faint longitudinal ridges, which are, however, always quite smooth. The actinal radioles are somewhat flattened and widened (more so in the large specimen), more or less fluted toward the point, but not serrate on the edges; they are slightly curved (Plate 15, figs. 1-2 and 7). The secondary spines are flat and pointed, appressed to the test. Those around the radioles are the largest, about 6 mm. long, the following about half that length, the remainder on the inner part of the Gucovambulweral plates only about 1 mm. long. The primary ambulacral spines are scarcely 3 mm. long, flattened and pointed like the others; the inner ambulacral spines are only about 0.5 mm. long. The spines on the apical system are likewise very small, the inner circlet of spines around the anal opening being somewhat larger. ‘‘Ampulle’’ are not found. The spines of the peristome, as usual, are somewhat curved. The spicules are of the usual type. The actinal tubefeet are provided with a well-developed sucking disk. In the abactinal tubefeet no sucking disk is developed. In the tubefeet on the peristome the disk and the spicules below it are more com- plicated, irregular, spinous plates. The pedicellariz, as stated in the Jngolf Echinoidea,® are in general similar to those of the genus Cidaris. The large globiferous pedicellariz (Plate 17, figs. 12, 13) have the valves terminating in a powerful end tooth above the large round open- ing; the stalk has no limb of freely projecting rods. The small globiferous pedi- cellarie have only a very inconspicuous end tooth; the opening is very large, reaching nearly to the basal part (Plate 16, figs. 4,10). They occur of different sizes, and the larger cannot always be distinguished with certainty from the triden- tate pedicellarie (Plate 16, fig. 5). These latter (Plate 16, fies: 3, 7,8, 13>Plate ti fig. 7) are long and slender (up to 1.5 mm. length of head), the valves joining Alone their edges in their whole length; the larger ones are rather strongly spinous at the upper end of the apophysis, and ihe blade is filled with irregular meshwork. The edges are thick, irregularly spinous. The color is as described by Clark; it ought only be remarked that in the larger specimen also the abactinal system is alnest white. According to Clark, the species is as yet known only from off the north- western coast of Cuba and from off Barbados, in depths of 125-205 fathoms (Blake; Albatross). I cannot give any additional information on this point. That the species has been confounded with Histocidaris (Porocidaris) sharrert is certain, since the type-specimen was found thus labeled in the British Museum, as stated in the /ngolf Echinoidea.* | Whether Agassiz has confounded it with His- tocidaris sharreri, I do not know; but until it has been definitely proved to which species the specimen of ‘ ’Porcidaris sharreri,”’ which was mentioned in the Blake Echini on page 13, as being ‘‘of a light greenish-pink color when alive, the spines white wit a delicate Groene -pink base,” really belongs, I would rather GP tI: ipr22: SOME WEST INDIAN ECHINOIDS. 5 suggest that it is C. micans. In any case that species was dredged by the Blake as is now stated by Clark. The genus Calocidaris, which was established by Clark for this species, is evidently very nearly related to Cidaris in the restricted sense (formerly Doro- cidaris). The characters pointed out by Clark are ‘‘the very broad and nearly bare median ambulacral areas, the remarkable color, and the smooth, polished prima- ries.’’ As shown here the ambulacra do not really differ from those of Cidaris. There thus remain only the color and the character of the radioles. This is cer- tainly not of much importance for a generic distinction—especially since Doctor Clark does not otherwise consider the characters afforded by the radioles as being at all of generic value, as is so conspicuously shown by his conception of the genus Phyllacanthus. Nevertheless, I think we can accept the genus, the radioles—in my opinion—affording characters of sufficiently high value for generic distinction. Compare my remarks on this matter in Die Echinoiden der deutschen Siidpolar Expedition (p. 49). Cn C. abyssicola the radioles also appear very smooth; a close examination, however, shows them to be finely striate and serrate—they are not ‘‘polished”’ as in Calocidaris.) Also the whole appearance of this cidarid is very characteristic. It thus seems to me that the genus Calocidaris may be valid; but it seems likewise beyond question that it is closely related to the genus Cidaris (Dorocidaris). TRETOCIDARIS BARTLETTI (A. Agassiz). Plates 2-3; plate 7, fig. 6; plate 14, figs. 8-9; plate 15, figs. 8, 12-14; plate 16, figs. 2, 12; plate 17 figs. 1, 6. Dorocidaris bartletti A. AGassiz, Bull. Mus. Comp. Zoél., vol. 8, 1880, p. 69; Mem. Mus. Comp. Zodél., vol. 10, 1883, p. 9, pl. 2, figs. 17-27, (not fig. 16).—R. Ratusun, Proc. U.S. Nat. Mus., vol. 8, 1885, p. 610; vol. 9, 1886, p. 261.—A. AGassiz and H. L. Cuark, Mem. Mus. Comp. Zoél., vol. 34, 1907, no. 1, p. 8, pl. 12 a, figs. 6-13. Tretocidaris bartletti Ta. Mortensen, Ingolf Echinoidea, pt. 1, 1903, p. 16, pl. x, figs. 23, 30; pt. 2, 1907, p. 169.—H. L. Crarx, Bull. Mus. Comp. Zoél., vol. 51, 1907, p. 203, pls. 8-9.—Tu. Mortensen, Echinoiden der deutschen Siidpolar Expedition, 1909, Ergbn.d. deutsch. Stidpolar Exped., XI, Zoologie, vol. 3, p. 47. Tretocidaris annulata Tu. MorteNsEN, Ingolf Echinoidea, pt. 1, 1903, p. 16, pl. 9, fig. 4; pl. 10, figs. 22, 31; pt. 2, 1907, pp. 169-170. This species, though it was not described before 1880, has had already a rather intricate history, and it has played a somewhat prominent part in the dis- cussion of the classification of the cidarids inrecent years. The history is as follows: Having at first probably been confounded with Cidaris abyssicola as suggested by Mr. Agassiz in the Preliminary Report on the Blake Echini it was established as a separate species of the genus Dorocidaris by him in the same paper. In the final report on the Blake Echini it was again described and figures were given of the spines and of parts of the test; but unfortunately this description is insuf- ficient and apparently the figures given are not all of this species. In the Ingolf Echinoidea (pt. 1), I established a new species, annulata, based upon an old specimen seen in the British Museum. This supposed new species differed from bartletti mainly in the structure of its test, the ambulacra having only a small secondary tubercle on each plate inside the primary tubercle, whereas figure 16, on the second plate of the Blake Echini shows the whole ambulacral area closely covered with secondary 6 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. tubercles, two distinct secondary tubercles on each plate inside of, and not much smaller than, the primary (in the description it is only said that ‘‘the median granulation [is] finer, than in the other West India species of the genus,’”’) the interambulacra having a distinct naked median space, whereas the figure shows no naked median space (in the description it is only stated that the interambu- lacral plates ‘‘are covered by a comparatively coarse, irregularly arranged secondary eranulation.”) I had at that time no reason to doubt the correctness of the figure given; the specimen examined in the British Museum, however, could not pos- sibly be identified with bartletti as there represented and thus had to be made a new species of the genus Tretocidaris, to which genus it was referred on account of its globiferous pedicellariw, which were essentially like those found in bartlett’. During my visit to the U. S. National Museum I had occasion to examine the specimens of T'retocidaris bartletti preserved in the collections of. that institution and I found that they had the same structure of the test as that described by me in Tr. annulata, not as shown in figure 16, of Plate 2 of the Blake Echini. Also a specimen examined in the collections of the Peabody Museum, Yale University. showed the same structure of the test. The result of these examinations was pub- lished in Part 2 of the Ingolf Echinoidea, pages 169-170, namely, that my T'reto- cidaris annulata was synonymous with Tr. bartletti, the quoted figure of the Blake Echini belonging to another species—or, in case this figure were correct, Tr. annulata must be maintained, and then all the specimens of Tr. bartletti seen by me in the U. S. National Museum and the Peabody Museum were not Tr. bartletta but Tr. annulata. In Agassiz and Clark’s memoir on the Cidaride (Hawaiian and other Pacific Echini) no mention is made of this question, but in H. L. Clark’s important paper The Cidaride,% page 203, it is pointed out that my Tr. annulata can not be distinguished from Tr. bartletti. Although no full description is given of the species, it appears from his remarks thereon that he regards the specimens in the U.S. National Museum as true bartlett2, and as he has had access to the type- specimen in the Museum of Comparative Zoology at Cambridge, this question has been solved. Of figure 16, on Plate 2, of the Blake Echini, which has caused the trouble, no word is said. Possibly it was made from a specimen of Cidaris blakei (A. Agassiz). Plate 14, fig. 7, represents part of an ambulacrum of this species. It willreadily be conceded that the similarity to the quoted figure from the Blake Echini is considerable; only the latter figure represents the inner tuberculation a little more regular than it isin C. blakev. One more argument speaks for the correctness of the suggestion that the figure represents really C. blakei, namely, that no other West Indian cidarid has the ambulacra thus tuberculated; also the part of the interambulacral area represented in the figure agrees fairly well with C. blakei, only the tubercles around the areoles are scarcely so prominent as in nature (see fies il, on Plate 2 of the Blake Echini, which gives a good representation of this struc- ture in C. blakei). In the Hawaiian and other Pacific Echini, the Cidaride, it is pointed out that the globiferous pedicellariz of Tr. bartletti may show a very considerable variation, @Published in December, 1907; the second part of the Ingolf Echinoidea was published in November, 1907. SOME WEST INDIAN ECHINOIDS. 7 examples both with an end tooth and without occurring even in the same specimen, and this fact was especially urged as an argument against the value of the pedi- cellariz in the classification of cidarids as set forth by me in the Ingolf Echinoidea. In The Cidaridee Doctor Clark figured a specimen of Tr. bartletti, which, as he later informed me, was the specimen in which the various forms of pedicellarie figured in the above quoted memoir (Plate 12a, figs. 6-13) were found. Now this specimen differs through its spines so much from the typical form of 7’r. bartletti that I have suggested (Echinoiden der deutschen Siidpolar Expedition, p. 47) that it may be a hybrid between Tr. bartletti and Stylocidaris affinis; the argument deduced from it against the classificatory value of the pedicellaria would therefore be invalid. The correctness of this suggestion is discussed on page 10. Thus runs the intricate Re of this species. Though it has been so much discussed, as yet no adequate description or sufficient figures have been given of it. I thus naturally wished to take the opportunity here to give the description and figures wanted and, accordingly, two specimens were sent to me together with photographs of the largest specimen in the U.S. National Museum (Plates 2-3). The Museum of Copenhagen had previously received a small specimen of the species, which has also been made the object of study on this occasion. The following description is thus based mainly on these three specimens; but, of course, my notes on the specimens examined during my visit to Washington and New Haven are also taken into account. Measurements. | | | Number of | Width of— | plates! | Diam- | Height. | Apical | Peri- | | Longest eter. |system. stome. | spines. | Inter- | Inter- | | Am bu- mbu- | | liar ambu- ee | ambu- | | lacra. ‘ lee lacra. | mm. | mm. | mm. mm. | mm. | mm. | mm. 29 | 16 | LAPe nee sls 3.5 14 | 55-56 | 6-7 | 60 | 27 [eer ath 135) Se S857 4] S25) 56-57; Wal 49 i tech 48 9 9.5| 2.2 7.5| 3940] 56] 18.5 The test is rather low, the height 54-59 per cent of the horizontal diameter; the abactinal side is rather flat, the apical system only slightly elevated; the sides are beautifully arched; the edge of the peristome not incurved. The ambulacra (Plate 14, fig. 9) are of the usual width, distinctly sinuate; close inside the primary tubercle each plate carries a small secondary tubercle at the lower edge, and between these two a very smali miliary tubercle (carrying pedicellariz) is generally found; the rest of the plate is naked, and there is thus a comparatively broad, wholly naked median space. In the largest specimen in the U. S. National Neen (68 mm. horizontal diameter) a small third tubercle has appeared inside the second on some of the ambulacral plates at the ambitus, but the naked median space remains as conspicuous as in the younger specimens.* On about 12-15 of the upper ambulacral plates as yet ponly the primary tuberele has a The figures (Plates 2-3) do not chow hin) of course; a figure of the specimen in ee view alone could show this feature. 8 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. appeared, and likewise some few of the plates at the actinal end of the area carry only the primary tubercle. This holds good for the larger and the smaller of the three specimens in hand; in the specimen of 27 mm. horizontal diameter the small inner tubercle has appeared on some of the plates near the apex and the peristome, but quite irregularly. The pores are separated by a rather broad wall, which is not at all elevated (Plate 16, fig. 12); the whole pore area is unusually flat and even, not distinctly sunken. The interambulacra have a comparatively broad naked median line, which is slightly sunken; this is also the case with the upper horizontal sutures. The areoles are unusually low; only the two lowermost may be confluent (in larger specimens probably more may be so). The upper tubercles are very distinctly crenulated, but only on the abactinal side. (Plate 14, fig.8.) The tubercles around the areoles are distinctly larger than those outside; these latter are few in number and only indis- tinctly arranged in horizontal series on the median part of the plate. The apical system is 48-54 per cent of the horizontal diameter of the test; the genital plates are almost rectangular, only slightly broader within than without; the outer edge is very little prominent; the ocular plates are rather large, heart- shaped, more or less broadly in contact with the anal plate. (Plate 15, fig. 12.) In the smallest of the three specimens at hand they are all excluded from the anal area. (Plate 7, fig. 6.) The periproct is covered with rather numerous small plates. The whole apical system is somewhat sparsely covered with tubercles; those on the ocular plates are generally rather characteristically arranged, forming an arched series along the outer edge, just inside the ocular pore; those over the pore are considerably smaller than those laterally placed. The peristome is from 42.5 to 45.5 per cent of the horizontal diameter, in the youngest specimen even 57 per cent; the interambulacral peristomial plates are quite regular; they do not reach quite to the mouth edge, but the adjoining ambu- lacral series do not, however, fully join at the inner edge. There are 11 ambulacral plates in each series in the specimen of 27 mm. The pores of each pair are placed nearly vertically (namely, one outside the other); the first pair is distinctly larger than the following. The radioles are well shown in Plates 2-3; and the figures 18-27, Plate 2 of the Blake Kchini likewise represent them very well. They are very characteristic, dis- tinctly striate, coarsely spinous in the proximal part, the spinelets diminishing and disappearing toward the point. It is a very peculiar feature that these spines are developed exclusively on the upper side of the radioles, the lower side remaining almost entirely smooth, the longitudinal strie being here only finely serrate (com- pare Plates 2-3). They are somewhat tapering, and the point may be somewhat widened. This form of radiole is evidently the typical form, but another form may occur in which the spines are not thus developed; the upper side of the radiole is then not more spinous than the lower side, the whole radiole being finely serrate along the longitudinal stri. Such radioles are figured in Plate 2, figs. 20 and 23 of the Blake Kchini, and according to Agassiz both forms may occur in one and the same specimen. I have not seen that myself. In the largest and the smallest of the specimens at hand the radioles are all of the typical spinous form, except some of the uppermost; but these are young radioles, not yet fully formed, without SOME WEST INDIAN ECHINOIDS. 9 ostracum. I might venture to suggest that the smooth radioles found by Agassiz in specimens with spinous radioles were really such young radioles. The third speci- men at hand, on the contrary, has all the radioles of the smooth form; the same is the case in the specimen figured by Clark. (The Cidaride, Plates 8-9.) There are, however, reasons for suggesting that this form of radiole does not really belong to the species bartletti, the specimens bearing them being probably hybrids (see p- 10). The radioles are banded with brown, the ground color being whitish; the coarse spinelets are white, including those on the brown bands, which makes them especially prominent. In sections the radioles are seen to have the ostracum covered with fine, unbranched “‘hairs.’’ (Plate 16, fig. 2.) In the smooth radioles these hairs appear to be somewhat less numerous. The actinal radioles (Plate 15, figs. 8, 13-14) are very little specialized, faintly serrate along the strie of the aboral side; the striz are very little developed on the adoral side and only toward the point. The secondary spines are flat and somewhat pointed; those around the radioles are distinctly longer and broader than the primary ambulacral spines (not nearly of the same size as mentioned in the description in the Blake Echini). The inner ambulacral spines are very small, not quite 1 mm. long; they scarcely reach the base of the primary ambulacral spines. These latter are about 3 mm., those surrounding the radioles about 4-5 mm. in length. The spines on the anal plates are rather large and are so bent as to cover the anal opening. Those on the geni- tal and ocular plates are smaller, especially the latter; the spines forming the outer series on the ocular plates, mentioned under the description of the tuberculation, are bent outward so as to cover the ocular pore. ‘Ampulle”’ are well developed on the abactinal spines, and also on those around the radioles. The spicules do not afford any specific features; they are of the form typical of cidarids, and are arranged in the usual way so as to leave a naked space for the nerve. The pedicellarie of this species have received considerable attention. The large globiferous pedicellariz are of the peculiar form described and figured in the Ingolf Echinoidea® with a well-developed end tooth and the opening reduced to a small pore. The stalk generally is provided with a limb of projecting rods, but this is not always distinct (see Plate 12a, figs. 12-13 of A. Agassiz and Clark; Hawaiian Echini, Cidaride). The small globiferous pedicellariz have, like the large form, a well-developed end tooth, but the opening is larger and triangular (Plate 17, fig. 6). As is often the case in Cidarids in which both large and small globiferous pedicellarie have (or lack) an end tooth, intermediates occur of which it cannot be said with cer- tainty whether they belong to the one or the other form, both forms varying con- siderably in size and also in the size of the opening. The tridentate pedicellarix (Plate 17, fig. 1) are simple, narrow, the valves joining in the outer half of their length; there are numerous cross beams in nearly the whole length of the blade. They reach a size of 2 mm. in length of head. In the Hawaiian Echini, Cidaride, Agassiz and Clark have figured a series of large globiferous pedicellariz: from a single specimen of Tr. bartletti (Plate 12a, figs. 6-11), showing a much larger degree of variation than described above, the aPt. 1, p. 16, pl. 10, figs. 22-23, 30-31. 10 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. variation ranging from the typical form to that with a large terminal opening and without an end tooth, resembling those of Stylocidaris affinis. Concerning this extraordinary variation I may first point out that the figure 6 in my opinion represents a young, not yet fully developed pedicellaria® and that figure 9 has very much the appearance of having the end tooth broken. But the figures 7 and 8 can not thus be disposed of; Doctor Clark has informed me that he is absoutely certain that they really belonged to the same specimen, and it is also said in the explanation of the plate that the form represented by figure 7 was quite common. ‘The specimen in which these different forms of pedicellarie were found is that figured by Clark in The Cidaridee Plates 8-9, as Doctor Clark has informed me, namely, a specimen with the radioles of the unusual smooth form, so different from the typical spinous form. Agassiz and Clark do not indicate that they have found the different forms of pedicellariz in any other specimen, and I, for my part, have found only the form with the small pore in all the specimens examined with spinous radioles; in the specimen with smooth radioles I have found a single globiferous pedicellaria of the Stylocidaris form among very numerous pedicellarie of the typical form. On account of the uncommon form of the radioles in the specimen figured by Clark and the fact that two different forms of large globiferous pedicellarie occur in this speci- men I ventured to suggest, in my work Die Echinoiden der deutschen Siidpolar Expedition (p. 47), that it is a hybrid between Tr. bartletti and Stylocidaris affinis. Having now had occasion to examine such a specimen myself, I feel strengthened in this opinion. On comparing this specimen with the typical form, one would at first refuse to regard the two as belonging to the same species, so different are they in appearance. But a close examination does not reveal any other features than the radioles by which to distinguish them, except the peculiar occurrence of the two forms of globiferous pedicellarie. I do not, of course, maintain upon such scanty material that it is proved that the form with the smooth radioles is really a hybrid, but it seems to me a natural explanation of this peculiarity. STYLOCIDARIS?” LINEATA, new species. Plates 4-6; plate 7, figs. 3-5; plate 14, fig. 10; plate 16, figs. 6, 9; plate 17, figs. 4, 8. The shape of the test is very like that of Stylocidaris affinis, so that in this feature or in the relative proportions of the parts of the test scarcely any difference between the two species can be found. The ambulacra alone afford a difference, which appears to be constant and thus of value as a specific character. In all the four specimens at hand each ambulacral plate carries only one small tubercle within and a little below the primary tubercle; there is thus a rather broad bare median space left between the two quite regular series of tubercles (Plate 14, fig. 10). In Sté. afinis this also holds good in the younger specimens, but in the larger ones each ambulacral plate (at the ambitus) carries another smaller tubercle at the upper edge of the plate, the innér series thus becoming irregular and the median naked space less conspicuous (Plate 14, fig. 1). This third tubercle makes its appearance at a @ Agassiz and Clark (Hawaiian Echini, p. 8) have mentioned this as being possible but not probable. » Concerning the name Stylocidaris, reference should be made to my work Die Echinoiden der deutschen Stidpolar Expedition, p. 52. SOME WEST INDIAN ECHINOIDS. 11 size of about 25 mm. horizontal diameter. It must, however, be admitted that this tubercle (and its spine) is sometimes very small and inconspicuous, even in the larger specimens. The number of coronal plates is virtually the same in both species. The apical system and peristome do not seem to afford any constant differences from St. affinis in structure or size. The radioles, on the other hand, afford a con- spicuous difference through their greater length, more than twice the horizontal diameter of the test in grown specimens. This, it is true, may also be the case in St. affinis, as pointed out by Clark (The Cidaride, p. 203), but, so far as I have been able to find, only in the young specimens; in those fully grown specimens which I have seen they do not exceed one and one-half times the horizontal diameter. The structure of the radioles also differs somewhat in the two species. In St. lineata the hairs covering the ostracum are more slender than in St. affinis and they are not anastomosing (Plate 16, fig. 9), while in St. affinis they are generally somewhat branched and may form anastomoses (see Jngolf Echinoidea, pt. 1, pl. 11, fig. 1; the statement made there, p. 36, that they do not form anastomoses, does not always hold good). The radioles are beset with numerous small, longi- tudinally arranged spinelets as in St. afinis. The secondary spines do not differ in length or shape from those of St. afinis, only the ‘“‘ampulle”’ are, perhaps, somewhat larger than in that species. The globiferous pedicellariz do not present any distinct differences from those of St. affinis; the tridentate pedicellariz, on the other hand, are characteristically different, as is best seen on comparing the two figures 4 and 14, Plate 17, represent- ing a tridentate pedicellaria of each of the two species. The space between the valves is distinctly narrower in lineata than in affinis; and the basal part of the valves is also different in outline. They are considerably larger in St. lineata up to about 1.5 mm. length of head, whereas in St. affinis they scarcely exceed 0.8 mm. The spicules are alike in both species. The color is white; against this ground color the brown median ambulacral and interambulacral line (to some extent also the horizontal interambulacral sutures), and a brown band over the middle of the genital plates, making a con- spicuous ring on the apical system, stand out very beautifully. The secondary spines are wholly white; the radioles are also mostly white, but they may some- times show a faint reddish tint, especially near the tip; there may even be traces of bands of this color. I dredged this species (2 specimens) in about 250 fathoms off Frederiksted, Santa Cruz (Danish West Indies), in January, 1906. In the U. S. National Museum I have seen additional specimens of it from off Havana, taken by the U.S. fisheries steamer Albatross in 1886, besides several more specimens from stations 2135 (Cat. no. 10753), 2152 (Cat. no. 7485), 2154 (Cat. no. 7476), 2157 (Cat. no. 7478), 2162 (Cat. no. 7482), 2319-24, 2327, 2336-37, 2342, 2345-49 (Cat. nos. 10709-10). These specimens are mentioned in Doctor Rathbun’s Catalogue of the Collection of Recent Echini in the U. S. National Museum, page 260, as Doro- cidaris papillata; on the labels of most of them, however, is found a question mark indicating that Doctor Rathbun was doubtful whether they were correctly referred to that species. The species evidently must be rather common in the West 26599°—Bull. 74—10——2 12 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. Indian seas and it is thus probable that it has also been dredged by the Blake and, likewise, included under Dorocidaris papillata. Whether Clark has included this species under “ Tretocidaris”’ affinis, I can not say; but in any case he must certainly have seen some of the specimens mentioned above, since he has examined the col- lection of cidarids in the U. S. National Museum. I have been in some doubt whether I should mention this form as a new species or only as a new variety of afinis. The distinguishing characters are certainly not very important, and the material at hand is small (I have not examined very closely all the specimens mentioned above as seen in the U.S. National Museum). Judging from the material at my disposal it would appear to be quite evident that we have here a distinct species; but Clark’s statement that affinis is so very variable in color makes me hesitate in creating a new specific name for this form. However, I have taken this course in view of the fact that the differ- ences in the ambulacra and in the tridentate pedicellariz seem to afford very good specific characters; in addition to which the length of the spines, the brown bands on the test, and the total lack of red on the secondary spines contribute to make this form appear very characteristic. Should it ever prove untenable as a separate species no great harm will have been done, for, in any case, it will certainly be necessary to keep it as a distinct variety. The reference of affinis to the genus Tretocidaris in Clark’s important work The Cidaride, I have criticised in my report on the Echinoidea of the German Southpolar Expedition, pages 51-52, to which work I may refer. I venture to hope that I have there made it sufficiently evident that this disposition of it was erroneous. The genus Stylocidaris was established there for the group of species related to affinis, which was made the genotype. In the Challenger Echinoidea Mr. Agassiz ascribes to C idaris cidaris (Doroci- daris papillata) an almost cosmopolitan distribution; the North Atlantic, from Norway to the Canaries, the West Indian seas, La Plata, the Philippines. The same distribution is still given for this species in his magnificent work The Panamic Deep Sea Echini (p. 228). In my work on the Jngolf Echinoidea I was able to restrict this enormous range considerably, finding the specimens from off La Plata and the Philippines to belong to widely different forms, none of them really being of the same genus as the ‘‘ Dorocidaris papillata,’ to which they were referred.? As for those from the West Indies, I thought they might really prove to be identical with the form from the Norwegian Sea and the Northern Atlantic (except- ing, of course, Stylocidaris affinis, which was also previously regarded only as a syno- nym of Cidaris cidaris). Having, however, no specimens of the West Indian form except two of C. abyssicola, I could form no definite opinion on the question. It is true that I had examined some specimens in the British Museum, but mainly for the pedicellarizw, and in their structure no reason was found for regarding the West Indian form as specifically different from C. eidaris. As for C. abyssicola I was inclined to regard it as a distinct species.’ After having examined a considerable number of specimens from the West Indies, Doctor Clark (The Cidaridz) comes to the conclusion that not only abyssicola a Ingolf Echinoidea, pt. 1, pp. 35, 170-172. dIdem, eat SOME WEST INDIAN ECHINOIDS. 13 is a distinct species, but also another distinct new species (C. rugosa) is found here, which has hitherto been confounded with C. cidaris, whereas the true C. cidaris (D. papillata) does not seem to occur in the West Indian seas at all. This results in a much more restricted distribution of C. cidaris, which accordingly occurs only in the Eastern Atlantic and the Mediterranean. The Challenger specimens from St. Paul’s Rocks which I have maintained to be true C. cidaris (Ingolf Echinoidea, pt. 1, p. 170), Clark supposes also to belong to C. rugosa. After the separation of C. rugosa from C. cidaris I do not venture to maintain that the St. Paul’s Rocks specimens belong to the latter species, as I have not examined the structure of the test in detail; the pedicellarize are not sufficiently characteristic in the different species to permit a definite answer to this question. C. cidaris would thus form one more species peculiar to the eastern Atlantic deep sea (besides Poriocidaris purpurata and Sperosoma grimaldii) a fact tending considerably to strengthen my view that this part of the Atlantic deep sea area forms a separate region. (See Ingolf Echinoidea, pt. 2, p. 187.) Having recently obtained some additional material of C. abyssicola and also a specimen of C. rugosa, I have taken the occasion to compare these forms carefully with ©. cidaris and to form an opinion of the question of their specific value. The result of my investigation is that I think rugosa is a distinct species, though I cannot agree with Clark regarding all the characters which he gives as distinguishing it from C. cidaris. That C. abyssicola is a distinct species also seems to me beyond doubt; but I think it necessary further to distinguish as at least a distinct variety a form with slender radioles hitherto confounded with C. abyssicola. Whether it will perhaps ultimately prove to be a species distinct from abyssicola I am unable to ascertain from the material at my disposal. A more detailed comparison of the two forms of (. abyssicola will thus be necessary. Also afew remarks on C. rugosa may not be out of place. CIDARIS ABYSSICOLA, var. TERETISPINA, new variety. Plate 7, figs. 1-2; plates 8-10; plate 14, figs. 2-4; plate 15, figs. 3-6, 9-11; plate 16, fig. 11; plate 17, figs. 2-3, 5, 9-11. Measurements of the Typical Form. a2 | Number of | | Width of— | plates. | Diame-| y7,; Apical | Peri- |_——-——_} | Longest ter. Height. system. | stome. | Inter | Tater | Tadioles. | Ambus ambu- | Ambus | ambu- * | laera. * | lacra. | | | | | mm. mm. mm. mm. mm. mm. | | mm. 32 2 | 165 | 135 | 35] 15 | 4445 | 6 | 58 2 anie 19 15 13.2 | 3.5 15 44 | 6 | 67 | | Measurements of var. teretispina. a7 27 22 19.5 5.2 | 22 | 51-53 | 67 68 36.5 | 21 17 15 4 17.5 | 53-54 | 6-7 34 36 | 20.5 16 14 le 53-54 67 | 43 32 «| 18 16 13.2 4 | 16 44-45 6 40 | | 14 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. In the relative proportions of the parts of the test there seem to be no constant differences, as is apparent from the measurements. In the general shape of the test there may perhaps prove to be a difference. The large specimen of the variety is distinctly pentagonal in outline, the interambulacra being rather convex at the ambitus, forming the (rounded) angles of the pentagon (Plate 10, fig. 2). In the specimen of 36.5 mm. horizontal diameter this feature is also indicated, though much less distinct than in the large specimen. Whether this feature is observable also in the two other specimens I can not state definitely, not having denuded them. The ambulacra are somewhat different, at least in the specimens before me. In the original description of abyssicola Agassiz says that ‘‘each plate carries a larger exterior tubercle with a smaller one nearer the abactinal edge, and sometimes a third and fourth miliary between the two.’ This description agrees entirely with the two specimens of the typical form before me—excepting that the small inner tubercle lies at the actinal edge (Plate 14, fig. 2). Considering, however, that, so far as I know, this inner tubercle (when only one is found) is elsewhere in cidarids never placed at the abactinal edge, but either in the middle of the plate or nearer the actinal edge, I think it not unreasonable to suggest that ‘‘abactinal”’ here is a lapsus calami for ‘‘actinal.”” In the variety I find the inner tubercle placed more in the middle of the plate, and the miliary tubercles (carrying pedicellariw) along the lower edge more numerous, forming, especially in the larger specimen, a com- plete series along the lower edge. (Plate 14, figs. 3-4.) In the interambulacra I find the median space distinctly broader in the variety than in the typical form. The deepening of the median line is distinct almost to the peristome, that is to plates 1 and 2 in the typical form, scarcely visible below the ambitus in the variety, that is to plates 3 and 4. The apical system does not seem to afford any constant differences. In the two specimens of 36 mm. horizontal diameter of the variety the anal plates send out a prolongation reaching the ocular plates, which are thus in contact with the periproct; in the two other specimens this is not the case. Also the shape of the ocular plates is somewhat variable; they seem upon the whole to be slightly larger and less prominent than in the typical form. (Plate 15, figs. 3, 6, 9.) The peristome shows no distinguishing features. The radioles afford the most conspicuous differences. In the typical form (Plate 7, figs 1-2; Plate 8) they are somewhat fusiform, and attain their greatest diameter “fat about one-fifth the length of the spine from the base,’’ as described by Agassiz (p. 254). In the variety (Plates 9-10) they are quite cylindrical and generally more slender. (In the large specimen they are, however, as stout as those of the typical form.) The actinal radioles (Plate 15, figs. 4-5, 10-11) are a little more widened in the variety than in the typical mn but his difference is not quite constant; also in the typical form they may be just as much widened (Plate 15, fig. 10). They are slightly curved and flattened on the proximal side. The edges are generally distinctly serrate, though scarcely so much as in the one figured in Plate 15, fig. 10. In transverse sections (Plate 16, fig. 11) the radioles are seen to be finely spinous; though they appear very smooth, they thus really differ conspicu- ously from those of Calocidaris micans, in which the ostracum is ae smooth.¢ « See Tgoly ingteene pt. 1, pl. 1 was 2 SOME WEST INDIAN ECHINOIDS. 15 The secondary spines do not present any differences. ‘‘Ampulle” are found in both the typical form and the variety, at least on some of the spines of the abactinal system; whether on all of them cannot be decided from the material at hand. Certain of the pedicellarie afford a rather good distinguishing character, namely, the small globiferous. In the variety they have the valves distinctly con- stricted toward the large opening, which is generally not the case in the typical form (Plate 17, figs. 2, 10); however, similar shapes may be met with occasionally in the typical form. In the variety, moreover, the small globiferous pedicellarize vary considerably in size, the larger ones being very like tridentate pedicellarix (Plate 17, fig. 3), as is also the case in Calocidaris micans. A very curious instance of a small globiferous pedicellaria with two heads was found in the typical form of this species (Plate 17, fig.9). The large globiferous and the tridentate pedicellarize (Plate 17, figs. 5, 11) are alike in both forms. The same holds good for the spicules. In the Hawaiian and other Pacific Echini, the Cidaride,* Agassiz and Clark give in Plate 12a, figures 1-5, a series of illustrations showing ‘‘the great diversity in the large globiferous pedicellarie in Cidaris abyssicola,”” on account of which it is deemed to be ‘‘unwise to lay any stress on their form as a systematic character” (p.7). Imay reply to this: First, that the figures probably all represent “small” globiferous pedicellariz, not those of the large form. Perhaps figure 1 represents a large one, though the small gland cavity decidedly points toward its being a “small” globiferous pedicellaria. Next I think that even though the small globi- ferous pedicellariz are very variable—I quite agree with Agassiz and Clark that they really are—the peculiar form with the constricted valves may be very useful as a specific character; judging from the figures 3-5 in the plate cited of Agassiz and Clark’s work I, would even suggest that the specimen from which these pedicel- lari were taken was one belonging to the variety teretispina. Regarding the color it can only be stated that the two specimens at hand of the typical form are quite white, the specimens of the variety more or less brownish. Whether they are differently colored in life must remain undecided for the present. It seems very probable that it is this variety upon which Clark has based his description of C. abyssicola.? The expression “‘median ambulacral area * * * almost wholly covered with small tubercles” certainly agrees best with the variety. Also the fact pointed out by Clark that ‘“‘the uppermost coronal plates do not carry primaries, and even the second ones may lack a well-developed spine,’’ decid- edly agrees better with the variety than with the typical form,’in which latter some of the upper plates have well-developed radioles in both the specimens at hand. Finally, the figures in the Revision of the Echini (Plate 1, figs. 1-4) to which Clark refers,’ seem to represent the variety; figure 1 alone with its thick radioles seems to represent the typical form, though the radioles are not so distinctly fusi- form. But in any case the original description gives some of the distinguishing characters—the radioles and the ambulacra—so excellently that it seems beyond question that it is the form figured here in Plate 7, figures 1-2, and Plate 8, which must be regarded as the typical Cidaris abyssicola. Regarding the variety described above, I am inclined to think that it will ultimately prove to be a distinct species, «Mem. Mus. Comp. Zool., vol. 24, 1907. b The Cidaride, p. 208. 16 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. but the material at my disposal is far from sufficient to decide that, especially in view of the fact that some specimens of the variety have the radioles as stout as those of the typical form. A close examination of a large series of these forms will be necessary to decide the question; for the present, however, it seems to me necessary to keep the variety distinct from the typical form. CIDARIS RUGOSA (H. L. Clark). Plate 14, fig. 11; plate 16, fig. 1. Dorocidaris rugosa WH. L. CLarK, The Cidaride, p. 210, pls. 4-5, pl. 7, figs. 5-8. The most conspicuous difference from C. cidaris (papillata) is evidently the more closely tuberculated median ambulacral area. Whereas in C. cidaris there is, even in very large specimens, only one secondary tubercle within the primary one, placed almost in the middle of the plate,* there are in C. rugosa generally two sec- ondary tubercles on each plate, the result being that the median space is wholly covered with tubercles, whereas in C. cidaris it is comparatively open (Plate 14, fig. 11 to compare with fig. 12). The median space is also conspicuously narrower in C. rugosa than in C.cidaris, as shown in the two figures cited, which have been drawn from equal sized specimens of the two species. That the median interambulacral space is broader in C. rugosa than in C. cidaris, as stated by Clark, seems to me to be scarcely a constant feature; but there is another distinguishing character in the interambulacra not mentioned by Clark, namely, that the tubercles around the areoles are more prominent than in (C. cidaris (compare Clark’s figs. 7 and 8, Plate 7). That the abactinal system is more uni- formly tuberculated in C. rugosa than in C. cidaris does, at least, not hold good in the single specimen at my disposal. The radioles are stated by Clark to be twice to two and one-half times the horizontal diameter. In the specimen before me, 32 mm. horizontal diameter, the longest radioles are 40 mm. Also in the specimens figured by Clark the longest radioles appear to be scarcely twice the horizontal diameter. In transverse sections the radioles do not differ from those of C. cidaris. The pedicellarize are mainly like those of C. cidaris. The lower edge of the terminal opening in the large globiferous pedicellariz is not slit up, as is often (always?) the case in (. cidaris. The tridentate pedicellarie (Plate 16, fig. 1) are slightly broader than in that species. In this species also one may find transitional forms between the tridentate and the small globiferous pedicellariz. In the place cited in The Cidaride, Clark mentions that I have identified seven specimens of this species in the U.S. National Museum as “‘Dorocidaris papillata” and another one as “Stereocidaris ingolfiana”’; on page 190 it is stated that I have identified a series of remarkably short-spined specimens of ‘“Phyllacan- thus baculosa” from Aden as “Cidaris metularia.”” “As M. did not clean an ambu- lacrum, it is not strange that he failed to see the very characteristic poriferous zones. But it is hard to understand how he overlooked the conspicuous purple spots on the collar of the spines.” Iam not going to defend my identifications of # In younger specimens of C. cidaris, up to about 30 mm. horizontal diameter, the inner tubercle is developed only on one side, irregularly alternating. SOME WEST INDIAN ECHINOIDS. lea these specimens—though I should like to examine the specimen labeled Stereoci- daris ingolfiana. During my short stay at the U. S. National Museum I had to use the time for investigations relating to my own special work. When I found in the collections of the museum specimens which were unnamed, or which I thought evidently wrongly named, I put a label in the jars with the name I thought the right one. But I had no time to spend for a more exact and entirely reliable iden- tification. What has here happened is a warning that one should never trust oneself to name a specimen without having examined it fully in regard to all its characters. I venture to think that among the specimens really examined in detail by me, and not seen only in a cursory way in foreign museums, such errone- ous identifications will not be found. Quite recently this matter has become somewhat more serious. Lambert and Thiery, in their Notes échinologiques I, Sur le genre Cidaris,” find in this case an argument against the use of pedicellariz in classification: “En négligeant les caractéres du test, on s’expose & des erreurs de détermination comme celles com- mises, d’aprés H. L. Clark, par Mortensen, l’auteur de cette classification.” IT may state here expressly that this case can in no way be taken as a proof against the value of the pedicellariz; it is not the pedicellaria which have led me to the false determinations (as far as I can remember I did not even examine the pedicellaria of the specimens of Phyllacanthus baculosa), but the fact that I did not examine the specimens more closely. ARZOSOMA BELLI Mortensen. Plate 11; plate 12, fig. 1. Arxosoma belli Tu. MortENsEN, Ingolf Echinoidea, pt. 1, p. 54-55, pl. 12, fig. 29; pl. 18, figs. 10; 11, 22. This species, of which a short preliminary description was given in the Ingolf Echinoidea,? I found represented by several specimens in the collection of the U.S. National Museum (labeled Asthenosoma hystrix). Having had some specimens sent to Copenhagen, I am at length able to give a full description of the species and to point out more clearly the affinities with the real Arzosoma hystrix and with A. fenestratum, as also with A. violaceum, which has also hitherto not been fully described or figured. A. belli is, moreover, perfectly recognizable from the preliminary description, the pedicellarize being really very characteristic for this species. The specimens examined are from the Albatross stations 2350 (off Havana, 213 fathoms; 2 young specimens) and 2655 (north of the Bahamas, 338 fathoms; 2 large specimens). In addition there is one specimen from Mayaguez Harbor, Porto Rico, 220-225 fathoms (the Fish Hawk Porto Rican expedition). The species is as yet known only from the West Indian seas (137-338 fathoms), not from the European side of the Atlantic, in contrast to A. fenestratum, which occurs on both sides of the Atlantic Ocean—at least I have been unable to distinguish the West Indian from the east Atlantic form from the material at hand. a Bull. Soc. Sci. Nat. Haute-Marne, vol. 6, 1909, p. 24. b Pt. 1, pp. 54-55. 18 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. Table of measurements. {Norr.—ac=the plates of the actinal side; ab= those of the abactinal side. Arxosoma belli. | Width at ambitus of— Number of plates. Diameter. 4 x Apleats sys Peristome. Ambulacra. ead Ambulacra. Interambulacra. chet | mm. mm. mm. mm. mm. 140 2 32 32(35ab)a\ 52(45ab)¢) ca 24(ac) ca 38 (ab) 17-18 (ac) ca 26 (ab) ca 12 ca 110 15 24 28 36 18-19 (ac) ea 35 (ab) 13-14 (ac) 25 (ab) 9-10 100 14-16 21 25 35 17-18 (ac) ca 30 (ab) 14-15 (ac) 19 (ab) 9 025 6.5 8 5 10 8-9 (ae) 11-12 (ab) 8-9(ac) 9-10 (ab) 45 620 5.5 7 4. 7.5 8-9(ac) 9-10 (ab) 8(ac) 8-9 (ab) 5 Arzxosoma fenestratum. ca 140 ca 22 35 35 48 25-26 (ac) ca 37 (ab) 19-20 (ac) 21-23 (ab) ca 14 ea ll5 ca 22 27 28 40 ca 21 (ac) ca 30 (ab) 14-15 (ae) 18-20 (ab) ca 12 ca 110 ca 18 27 28 40 20-21 (ac) ca 28 (ab) ca 15 (ac) ca 22 (ab) ca 12 Pd Arzxosoma violaceum. eca 150 | (?) | ca 30 | “ca 30 ca 58 ca 34 (ac) ca 23 (ac) ca 12 Calveria hystrix. ca 165 22 ca 33 39 57 ca 35 (ac) ca 38 (ab) 26 (ac) 30 (ab) ca 13 ca 125 15 25 29 43 ca 25 (ac) ca 38 (ab) 17-18 (ac) 26-28 (ab) ca 12 ca 105 ca 17 25 23 37 23-24 (ac) ca 35 (ab) ca 20 (ac) ca 27 (ab) ca 14 623 5.5 7 5 8 8-9 (ac) 15-16 (ab) 9 (ac) 12-13 (ab) 4 a Above the ambitus. > Without genital openings. ¢ Too badly preserved for counting the abactinal plates. The present specimen is not the one figured on Plate 13, fig. 1. See explanation of this plate. : The measurements and enumerations given here show clearly that, as regards the relative dimensions of the different parts of the test, there are no very reliable differences to be found between A. belli and the other three species from the Atlantie with which it must be compared, namely, A. fenestratum, A. violaceum, and Calveria hystrix. The last upon the whole appears to have a somewhat larger number of ambulacral and interambulacral plates, and A. violaceum likewise seems to have a proportionately larger number of coronal plates than A. bellr. Regarding the shape of the plates there are evidently some rather important differences. Professor Bell, it is true, maintains? that these differences are aoe unreliable, all transitional forms occurring. Since, however, he does not hold « fenestratum as specifically different from C. hystrix (of which uhere is not the eae 2 On the Echinoderms collected by the S.S. Fingal in 1890 and by the 8.8 Saaeen in 1891 off the west coast of Ireland. Proc. Roy. Dublin Soc. (n.s.), vol. 7, 1892, p. 528, mi 25. SOME WEST INDIAN ECHINOIDS. 19 est doubt), one can not feel sure that the specimens examined by him are really the same species—on the contrary, it is beyond doubt that both hystrix and fene- stratum are among them, perhaps also violaceum—and thus his statement loses its weight. In fact, I find, after having examined a rather considerable number of these forms (especially hystrix), that the shape of the plates and the extent of the mem- branous interstices between the plates is not so very variable. Thus in C. hystrix I never find the wide membranous spaces between the plates so characteristic of A. fenestratum; A. belli in this respect comes near to A, fenestratum, though the membranous spaces are not quite so conspicuous; the same holds good of A. violacewm. Instead of giving long descriptions I think it is sufficient to refer to the figures, Plates 11-13. The most conspicuous difference is found in the arrangement and size of the primary tubercles of the actinal interambulacra. (Plate 11, fig. 2 and Plates 12-13.) In A. belli there are near the middle line two arched series of large tubercles, one tubercle to each plate. In the other species there is certainly something cor- responding to this, but the series are less curved, and there is generally a tubercle only on every second plate. Further, in A. belli these tubercles are larger than in the other species; in A. fenestratum they are not much smaller, but in A. violaceum and in C. hystrix they are considerably smaller. In the larger specimens some large tubercles appear between the marginal and the inner series, and here again the same fact holds good: Larger and on each plate in A. bella, smaller and not on each plate in the other species. In the abactinal side of the test, as well as in the apical and oral systems, I do not find any reliable differences, in size or structure, between the four species. In the two young specimens of A. belli the apical plates are still in contact, and the genital openings have not yet appeared. The spines do not seem to afford any reliable differences either. In the speci- mens of A. belli before me all the primary actinal spines are broken; in the specimen of 25 mm. horizontal diameter only a single spine has kept the hoof; judging from this the hoof is not especially large in this species, as is also the case in the other species.’ The miliary spines, those on the actinal as well as those on the abacti- nal side, have a small (poison) gland at the point. The tubefeet are as in the other species. The pedicellarie afford the most conspicuous differences as shown in the original description.© Tetradactylous pedicellarie I have been unable to find in any of the specimens of A. belli at hand; that they will prove to occur also in this species I can searcely doubt. The tridentate pedicellariz, so very characteristic that the species may be at once distinguished thereby (especially the small form), have been sufficiently described and figured in the Ingolf Echinoidea. (Pt. 1, p. 55, pl. 13, figs. 10, 11, 22.) The large form (fig. 10) I have not found in any of the specimens at hand. I have nothing to add concerning the triphyllous pedicellaria. The a'There may, however, be some inconsistency in this character; some of the plates may want the large tubercle, but still insuch cases this series of tubercles is generally more prominent and regular than in A. fenestratum. bI may note that in none of the European specimens of 4. fenestratum at my disposal has the hoof been preserved, all the primary actinal spines being broken. ¢ Ingolf Echinoidea, pt. 1, p. 55. 20 BULLETIN 74, UNITED STATES NATIONAL MUSEUM. spheridia are more globular than in A. fenestratum; they continue far up the abactinal side. The color is violet, more or less intense; in the two small specimens the color has almost totally disappeared. This species is evidently most nearly related to A. fenestratum, from which it is, however, easily distinguished by means of the pedicellarize* (especially the small tri- dentate), and the arrangement of the tubercles of the actinal interambulacra. The color of A. fenestratum—though generally more brownish—may be as violet as that of A. belli (aleoholic specimens of A. fenestratum, however, have mostly lost all color). From A. violaceum the species is still more easily distinguished by the same characters and also by the color, which is much more intense in this species. Finally from @. hystrix it is at once distinguished by the color (C. hystrix is always beautifully red, retaining the color in alcoholic specimens), the pedicellariw, and the structure of the test. On examining the entire series of ‘“ Asthenosoma hystrix’ from the Caribbean Sea preserved in the U. 8. National Museum, I have found the specimens to be either Arxosoma fenestratum or A. belli, while the true Calveria hystric was not found among them. It is thus very probable that this latter speciés does not occur at all on the American side of the Atlantic. In my work on the /ngolf Echinoidea ’ I made the species hystrix the type of a separate genus, to which also the Asthenosoma gracile A. Agassiz was referred. The name Calveria of Wyville Thomson was restored to this genus following Wyville Thomson in his work on the Porcupine Kchinoidea. In his Panamic Deep Sea Echini (p. 84) Mr. Agassiz pointed out that the name Calveria hystrix was originally given to a starfish (the one known as Aorethraster hispidus Wyville Thomson), a fact which Thad overlooked. Dr. F. A. Bather in his paper The Echi- noderm Name Calveria hystriz® gave the complete history of the name, which proves that Calveria can not, on a strict application of the priority rule, be used for the genus to which it was applied by me; that the species name hystrix likewise can not be used for the echinoid in question, as maintained by Doctor Bather, I am not inclined to admit. Accordingly, the genus Calveria as circumscribed by me ought to have another name, if the genus can be maintained. Mr. Agassiz, in the work quoted, does not recognize this as a valid genus and still maintains the two genera Phormosoma and Asthenosoma in the wide sense, as they are used in the Challenger Echinoidea.* Considerably more weight must be ascribed to the fact that Professor Déderlein, who otherwise agrees with me in the subdivision of the two ‘“‘genera’’ Phormosoma and Asthenosoma, thinks it doubtful whether the genus ‘‘ Calveria”’ can be maintained. ‘‘Auf das Fehlen einer bestimmten Pedicel- larienform einen generischen Unterschied zwischen sonst sehr nahe verwandten Arten aor description and figures of pedicellarie in }. (Samespecimen as Plate 3.) PuateE 3. Tretocidaris bartletti (A. Agassiz). Actinal side. X43. (Same specimen as Plate 2.) PuateE 4. Stylocidaris lineata, new species. Actinal side. Natural size. (Same specimen as Plates 5 and 6.) PLATE 5. Stylocidaris lineata, new species. Abactinal side. Natural size. (Same specimen as Plates 4 and 6.) PLATE 6. Stylocidaris lineata, new species. Side view. Natural size. (Same specimen as Plates 4 and 5.) PLATE 7. (All figures natural size.) Fras. 1-2. Cidaris abyssicola (A. Agassiz). 1. Abactinal side. 2. Side view; same specimen. 3-5. Stylocidaris lineata, new species. 3. Side view. 4. Actinal side. 5. Abactinal side; same specimen. 6. Tretocidaris bartletti (A. Agassiz). Young specimen. Abactinal side. PuaTE 8. (Both figures natural size.) Tic. 1. Cidaris abyssicola (A. Agassiz). Actinal side. 2. Cidaris abyssicola (A. Agassiz). Side view. PLATE 9. Natural size. Fics. 1-2. Cidaris abyssicola, var. teretispina Mortensen. 1. Actinal side. 2. Abactinal side; same specimen. Puate 10. (Both figures natural size.) Fic. 1. Cidaris abyssicola, var. teretispina Mortensen. Side view. (Same specimen as Plate 9.) 2. Cidaris abyssicola, var. teretispina. Actinal side; same specimen. Puate 11. Fics. 1-2. Arxosoma belli Mortensen. %{%. 1. Abactinal side. 2. Actinal side; same specimen. Figure 1 is made up from two different photographs; the left side was made to show the undenuded part of the test, the right to show the denuded part as clearly as possible, the color of these two parts contrasting so much as to make it impossible to represent both parts clearly in the same photograph. PuateE 12. Fic. 1. Arxosoma belli Mortensen. Actinal side. Natural size. 2. Arxosoma fenestratum (Wyville Thomson). Actinal side. X 3. SOME WEST INDIAN ECHINOIDS. Qi Piate 13. (Both figures x ?.) Fie. 1. Arxosoma violaceum Mortensen. Actinal side. The specimen was received ina very bad condition, denuded, flattened, and dried; it has thus been impossible to examine other features than those of test structure, and the identification is therefore given with a little reservation. Fie. 2. Calveria hystrix (Wyville Thomson). Actinal side. Puate 14, Fig. 1. Stylocidaris afinis (Philippi). Part of ambulacrum x 7, 2. Cidaris abyssicola (A. Agassiz). Part of ambulacrum x 6.8. 3. Cidaris abyssicola, var. teretispina Mortensen. Part of ambulacrum (from the specimen repre- sented in Plate 10, fig. 2) x 5.8. . Cidaris abyssicola, var. teretispina. Part of ambulacrum X 5. . Calocidaris micans (Mortensen). Interambulacral plate x 4. . Calocidaris micans (Mortensen). Part of ambulacrum 5. . Cidaris blakei (A. Agassiz). Part of ambulacrum 6. . Tretocidaris bartletti (A. Agassiz). Interambulacral plate x 6. . Tretocidaris bartletti (A. Agassiz). Part of ambulacrum x 8.5. 10. Stylocidaris lineata, new species. Part of ambulacrum X 7.5 ll. Cidaris rugosa (Clark). Part of ambulacrum X 8. 12. Cidaris cidaris (Linneus). Part of ambulacrum from a specimen of 33 mm. horizontal diam- eter of test, corresponding in size to the specimen of C. rugosa, from which fig. 11 was made X 8.5. Cor SD oP Puate 15. Figs. 1-2. Calocidaris micans (Mortensen). Actinal spines x 7. (Compare fig. 7.) 3. Cidaris abyssicola, var. teretispina Mortensen. Apicalsystem. From aspecimen of 47 mm. h.d. X 3. (Compare fig. 6.) 4-5. Cidaris abyssicola (A. Agassiz). Actinal spines X 7. (Compare figs. 10-11.) 6. Cidaris abyssicola, var. teretispina Mortensen. Apicalsystem. From a specimen of 36 mm. h. d. X 2.8/1. (Compare fig. 3.) 7. Calocidaris micans (Mortensen). Actinal spine X 7. (Compare figs. 1-2.) 8. Tretocidaris bartletti (A. Agassiz). Actinalspine X 8. (Compare figs. 13-14.) 9. Cidaris abyssicola (A. Agassiz). Apical system X 2.8. 10-11. Cidaris abyssicola(A. Agassiz). Actinalspines X 7. (Compare figs. 4-5.) 12. Tretocidaris bartletti (A. Agassiz). Apical system X 5.5. 13-14. Tretocidaris bartletti (A. Agassiz). Actinal spines X 8. (Compare fig. 8.) Puate 16. Fic. 1. Cidaris rugosa (Clark). Valve of tridentate pedicellaria. Side view X 60. 2. Tretocidaris bartletti (A. Agassiz). Transverse section of spine X 595. : 3-5. Calocidaris micans (Mortensen). Valves of pedicellarie. 3. Tridentate pedicellaria from the inside. 4. Small globiferous pedicellaria; side view. 5. Small globiferous (?). Side view X 60. (Compare figs. 7-8, 10, 13.) 6. Stylocidaris lineata, new species. Part of ambulacral plates X 35. 7-8. Calocidaris micans (Mortensen). Valves of tridentate pedicellarie. 7. Side view; 8, from the inside 60. (Compare figs. 3-5, 10, 13.) 9. Stylocidaris lineata, new species. Transverse section of radiole >< 55. ; 1G. Calocidaris micans (Mortensen). Valve of small globiferous pedicellaria. Side view 60. (Com- pare figs. 3-5, 7-8, 13.) ; i ll. Cidaris abyssicola (A. Agassiz). Transverse section of radiole X 55. 12. Tretocidaris bartletti (A. Agassiz). Part of ambulacral plates x 30. ; ; 13. Calocidaris micans (Mortensen). Valve of small tridentate pedicellaria. Side view 60. (Com- pare figs. 3-5, 7-8, 10.) 14. Calocidaris micans (Mortensen). Part of ambulacral plates X 24. 26599°—Bull. 74—10——3 28 Fie. 1. 10. Tt. 12. 132 14. BULLETIN 74, UNITED STATES NATIONAL MUSEUM. PLATE 17. Tretocidaris bartletti (A. Agassiz). Valve of tridentate pedicellaria. Side view X 50. (Com- pare fig. 6.) . Cidaris abyssicola, var. teretispina Mortensen. Valve of small globiferous pedicellaria X 60. . Cidaris abyssicola, var. teretispina Mortensen. Valve of small globiferous pedicellaria < 60. (Compare fig. 5.) . Stylocidaris lineata, new species. Tridentate pedicellaria x 60. . Cidaris abyssicola, var. teretispina Mortensen. Valve of tridentate pedicellaria, side view x 40. (Compare fig. 3.) . Tretocidaris bartletti (A. Agassiz). Valve of small globiferous pedicellaria x 70. (Compare fig. 1.) . Calocidaris micans (Mortensen). Valve of tridentate pedicellaria. Side view x 45. (Compare pl. 16, figs. 3, 7-8, 13.) . Stylocidaris lineata, new species. Valve of tridentate pedicellaria. Side view X< 60. . Cidaris abyssicola (A. Agassiz). Two-headed small globiferous pedicellaria x 60. Cidaris abyssicola (A. Agassiz). Valve of small globiferous pedicellaria x 60. Cidaris abyssicola (A. Agassiz). Tridentate pedicellaria < 35. Calocidaris micans (Mortensen). Valve of large globiferous pedicellaria. Side view x 60. Calocidaris micans (Mortensen). Large globiferous pedicellaria < 40. Stylocidaris affinis (Philippi). Tridentate pedicellaria x 60. NING a exes Page. abyssicola, Cidaris.......-....-. 1,5, 12,18, 15, 23 var. teretispina, Cidaris.............-- 13 Neesteibellidiferasos.cn.j.- jeer 24 AGUGUS EH ChINUBs seen. s= se fo e erates -ital= = 23, 25 WWéropeirostrata. -- 2/ae.0-4/-6 2-2-2 >-1= Rises 24 IATGrOpsis TOStra tata eee eile nie = 24 PUTIN eC A UTUS See re oso 2 = lala leleiete a= 23, 25 Stylocidanist=-c=e-ceeectienie- tr 7, 10, 11, 12,23 retocldarisucscesseenecec seer eee 12 Agassizia excentrica........-.------------ 24 albida, Trigonocidaris.......--------------- 23 alexandriaMchinus 12. 4-eee -scass-ees 23, 25 alltaes BIISSOPSIS year e712 ee lnicieae e eieeie 24 annulata, Tretocidaris. .....-.------------ 5,6 antillarum, Aspidodiadema.......--------- 23 Dermatodiadema...-......-.-------- -- 23 Diadema seen se eee sess crass sice eis 21, 23, 25 IN SeOROMAE Somes cece ce cieie te we eleiae aerate aievotoes 20, 21 [Wellies etre crear saises-lteiaetar aisle = 1, 17, 23 fenestrabuM=- srs = 5 17, 18, 19, 20, 21, 23, 25 WOECAMNS 6 socesdaBeastesacocs= 17, 18, 19, 20 Arbacia punctulata....-.-.-.------------- 23 Aspidodiadema antillarum .....-.--------- 23 NACOD YM ayer Scisieijciet= ig eign aie 23 IApthenosOMal: = «ae enc se eiinie === 20 gracile. ..--2-.-22---2- 222-2 +282 20 iystrin ees Sean en eet 17, 20, 25 atlantica, Brissopsis....-.----------------- 24 atlanticus, Psammechinus....-------------- 23 atropos, Moira........---------+----+----+--- 24, 25 Spatangus.......------------+-+-+---- 25 baculosa, Phyllacanthus.......------------ 16 bartletti, Dorocidaris. .-.-.--------------- 5, 23 Pretocid allseese sees seer oe eee ents 1, 5, 23 belli, Arseosoma. ...-----------+-+-+----- 1, 075.23 bellidifera, Aceste......------------+-+---- 24 blainvillei, Psammechinus...-..----------- 23 blakei, Cidaris. .....--.--------+--------> 6, 23 Dorocidaris. . ...--.------------------ 23 Brisaster fragilis.......-.-----------+----- 24 Brissopsis alta.......------------+2+-250077 24 Atlantica cesese sees ec se eee a= 24 Clonpataey cos =. asic -ais\= iin cis 24 yriferde teri. eric =lsiocfemie 21-2 - o> 24, 25 Page. Brissusminicolorstyeeceeesee an oer ore 24 Calocidarisies: Saasseetiee csecccre soe eee 5 MICANS- Aso eee as Sas oer 12, 14, 15, 23 Galweriame ire cient nce eae een elaeeeees 20, 21 gracilishaye- See Cee eee 21 IY BGY UK see oe et terer at =ee 18, 19, 20, 21, 23 caribbearum, Rhynchopygus.....-.-.----- 24 @idarisie ae. seo eee ee setae 3, 4,5 abyssicola sacs ee eer 1, 5) L258 80,20 abyssicola, var. teretispina........-.--- 13 blakels.3 ch oec0 12 ee eer 6, 23 @Ubintiinen seponestoncaanoc 1S; 2 aS HG S25 metulariaesesenelse == ere ele aoa 16 papill ata aisemcmses tateltal elaine 16 PUP ORAS ee onion te el 1, 13, 16, 23 tribuloidessseeeeeee eee eee 23 Clypeaster latissimus. ..-..--------------- 24 Tavenel lines sescereeeessas ceo 24 subdepressus........-----+---+---+---- 24 Ceelopleurus floridanus. ...-.-.----------- 23 Conolampas sigsbei. ..-.--.---------------- 24 cordatum, Echinocardium......-..--.----- 24, 25 cristatus, Paleeopneustes.....--.----------- 24 cubensis, Hemipedina. ......-.----------- 23 depressa, Echinolampas . .-..---------- ais 24 Dermatodiadema antillarum. .......------ 23 Diane Mae eae ws sate es eleletet aeration 21, 22 anti larumiee ee osoeseee eee DI 23520 MEXICADUM secs ce wler<:[e = settee eee t= 21 Feb ein Were nepmooracaeesos 5 oseracHoC 22 BetOSUM os, oct a= c.-bese nie seller 21, 22 DOrOCiGAaTIS.. «2-0 -/=/e 5-1 ee ee a= 5 bartlétticscccot ceneceiss ee eon 5, 23 Plakel= -coscieces = setae ee ee wter 23 TICADB &cteisinie #iaj-tere ie stot oetarete ae totale eater 2 papillata.....-.------ 1, 3, 11, 12, 13, 16, 23, 25 TUGOSA. .-- 2-2-2 0- 2 een ee erence o= 16 drébachiensis, Strongylocentrotus. .....--- 24,29 Echinanthus rosaceus. . . - ---------------- 24 Echinarachnius parma...-.--.--------+----- 24 Echinocardium cordatum. ...---.------+--- 24, 25 fla VeESCONS = 5 a 52-22. ss-e2 cease 21 Hucidanis)tribuloides..,....s-2.--2222-22ee 23/25) |;mnieans, Calocidaris)a.:- 2. <<... stack 12,14, 15, 23 e@xcentrica, Apassizians sen ccs- asec a eee 24 Worocid aris: 22 sae saa saeee eer ee eee 2 expercitus; Hemiaster <3. 4. -2c50-<25 acne 247 "nich elina WENCopelssescceiaseteeee a oteenee 24 fenestratum, Arzeosoma .... 17, 18, 19, 20, 21; 23,25 | micrasterioides, Rhinobrissus......... .... 24 flavescens, Echinocardium ...............- 245 \imoirandaPourtalesiavce o..see erate act eee 24 floridanus, Coelopleurus..............--.. 234) eMoraattOpOSasas- ta. ele sence eee eee 24, 25 ITaPIIS MBMSAStOL = sana ject eee eee 24; | maresianus,.\Urechinuses- 1. 5-1/2 seco ee 24 iHomolampasi. 343-212 - see enone 24: |) Neolampas rostellata 2.2... --..:--:--24.58 24 chizaster st = sects atest ee eee 240 MOrvericus. LChINUS ss2<- ceases eee ee 23, 25 Genocidarisimaculatae ccs ses sae ee aoe 23) \orbigmyanus: Schizaster=.-asscece.- sooo 24 goesiana, Saleniae: -22-seise cncusteeee ce 23), Palseobrissus hilgardii..c-.--:-eaeaeesoee 24 gracile, Asthenosoma..... 2ccc524-o22s% sec 20 | Paleeopneustes cristatus.................- 24 gracilis; Calveria-d222..s-h..cse et se eee 21 IDB UTE Ke here oe tee aisle tse esernelee tape ee 24 CHWS aces aee eee Sisjs Vee ee ais stank 23 | Paleotropus josephine ..................- 24 grandiporus, Echinocyamus............... 24 | thomson e....)./5sccne ce eee eer eee 24 grimaldii, Sperosoma....................- 13,21 | papillata; Cidaris’... 22. 2.522 cscccssecet oe 16 Habrocidanisiscutatal.-2- sass se. esas 23 Dorocidaris.......... 1, 3, 11, 12, 18, 16, 23, 25 Hemiaster expergitus ...................-. 24 | parma, Echinarachnius................... 24 Ten tai ede he ak Se aah Ogu lepattersoni; Waleniay: sc sss0 a5. seo eee 23 Hemipedina cubensis ....................- 23 | pectoralis, Metalia ........................ 24,25 hilgardi, Palseobrissus ....................- 24 Spatangus -...-......-.--.-.-2-2-22-. 25 Hipponod:esculenta-s.--5--. 0s «-2-4éeeh 24 | pennatifidum, Echinocardium ............ 24 hispidus, Korethraster.................... 20, 21 Periaster limicola ...........2.22-22--2++-: 24 ustocidarisisharrert.-.--2-/s25-2 soeo ee oe 4,23 petersi, Hygrosoma .......-.....-- .---- +2. a Tomcat: iPhormosomaseces sa: case ace a eee 20 DASHragUIge Eee ce memea=s eee 24 Hygrosoma petersi Placenta Sa ey Se nE it GAGA Saab 23, 25 yg POLOISI noe aac ees eec aon 23 : BISEDelon sacar stn REC ee 23 hystrix, Asthenosoma Sielseiela snsstehe sama WTS LO R25 RATT TIS toh an To a laa 23 Calveriay eee mcene 2 eee sea. 16,09; 20K21.23 Phyliscanthus 46 20k: eee Rae 5 Palzopneustes. ve rete eet eect eee eee DAI OTST alone eat eben eee oe MUI 16 ingolfiana, Stereocidaris:-)...0.- 2... 2.2.2 16, 17,23 | placenta, Phormosoma................... 23, 25 jacobyi, Aspidodiadema.................. 23 || Podocidaria.sculpta‘ss.0:.. 2.4.4.2 y-s eee 23 Jelireysi) Pourtalesiawsssssss-ecsee esses 24, 25 BCUTALSS mirercicve)issclersatsis Saree eee ee 23 INDEX. 31 Page Page. Moriocidaris)purpurata\-/----2- --\42 2 ss-=—- 13 | spatangoides, Macropneustes.............- 24 Porocidaris sharreri ............. Baten 41208 |) S pate ous aire DOS sees eye ne eee en ae 25 iPountalesianjetireyslise se ty. se eee = 24, 25 | pectoralisy 5 Re. 20s. eee ee eee 25 MILAN AE seme eee ese ls Se Satins Oe Ss 24 | DUDPULCUS Scena ale ee ae ee 24, 25 wandeli... 2401S perosomaxonnmal dilasee eae reset ee eee 13321 Psammechinus atlanticus 23 | Stereocidaris ingolfiana..............-. 16, 17, 23 blainvillei ss. oe See ee ye sak 23 | Strongylocentrotus drébachiensis..........- 24, 25 punetwiata, Arbaclaecns seq. cess <= 23 al Stvlocidarigss] see een eee es 10, 12 purpurata, Poriocidarise<-—-<.- 225.42. ---< 13 | affinise sacs eee eee 1, LO ye, 23 purpureus, Spatangus.........--..--.-.--- 24, 25 | Jineata’= 2 AS pe set nee cee ee 10, 23 pusillus, Echinocyamus..-....-.-..-------- 24, 25 | subangularis, Echinometra.............-.-- 24 yeastridesinrelicttisssnsere- secon aes ee a= 24 | subdepressus, Clypeaster....-..........--.- 24 ravenellii, Clypeaster-......---. we ateicyes ee 24 | Temnechinus maculatus...............---- 23 TENCHUA eV PAstnid Cease cee =e sala e 24 | Memmocidarista scr eee eee een eee 3 Rhinobrissus micrasterioides. ....-...----. 24 | teretispina, Cidaris abyssicola, var......... 13 Rhynchopygus caribbeearum..........-.-- 24) testudinata;, Melita ~~. 22-222 eee 24 TOsaceuss Bchinanthusse ssc esos =e a 24. | thomson, Palseotropus:-2-2-----------2+--1 24 rostellata., Neolampas..cess---- ses 42-5 24 | Toxopneustes vdriegatus. ..........-.-.-.- 23 rostrata, /ACrOpers. ss sssanesss--s=5eece= 945 Tretocidarishs-ce+-s.sc2 temas sae oes = eee I Oe INGPOPSISe sea -o siole ate oie asalas oi sicie sis. oe 24 QING! sn ansi-jiset sea anal Sete eats 12 MU POSAay Ol CALIS = eres yee ee 1, 13, 16, 23 | annulata 6 Worocidariswasca ses esc cesieese ance 16 bartletti Saleniay@Oesiama ese. ccseeateis cies sl = es5 ZSatribuloid ess Cid anise eee eseaeee eee see 23 ALE RSOM Tea yee oreo eet cee hiet)-relel= ais 23 UCId ans: ereseete er eee eee eer 23, 25 varispina. ... -- [prtesttttessessseeees 23 | Trigonocidaris albida...............-+----- 23 Salenocidaris Varispina....----------2----- 23 Tripneustes‘esculentus:--- 2-02-4224 --) == - 24 saxatile, Diadema.........--.--.--------- 22 | Tromikosoma keehleri.............-..----- 28 Schizaster fragilis. ..-.-.-++-+++-+++++++++--- 24 TuNICOlOL) BTISSUSS sees eee ae ee eee eee 24 orbignyanus. eee Pia ance ae aS 2 uranus. hormosomaes--cessa-ese- oe eee se 23 sculpta, Podocidaris ROR CO Eee Cae SE a (Wnechinusmareslanusssses---scsese see eeiase 24 BGutatay Hl abrocidaris. sa=-.- 4 --eeseee = ao s PR Maree ney, eatb. Nel oobi bers 93 | Variegatus, Toxopneustes.....-...--------- 23 semilunaris, Echinoneus........-.-------- 24 See Salenia SET So aie aie rhe sere aa ze BetosumemDigd ema societies = 2122 Salenocidaris SE apy Ce ees Th 23 sexforis, Mel baer tors porer eter srovsaretaces 24 ventricosa, Meoma.........------------++-- 24 sharreri, Histocidaris.............--------- 4,23 | violaceum, Areeosoma...-..---.----- 17, 18, 19, 20 Oral rie ee ane ee 4,23.| viridis, Echinometra.---..--.-.--.----.---- 24 Bigsbels Conolampas..s.. 1-12 clases so =/-\anlariar0 242) 2 Ye a2 C ey 2 “a ea F 2 ee SI 2 tals S990) ig” 299. Soe ado 2“ CS ie? we. sos, def Mies ee aD oa , Ga os oe > Fe De ee 2 2 De? 2 @ 2-394 @ 22%, ge? a ay “@ eose-.ge9 (209 29 OI, oo Q. shhe) soos). ee a _ y aa — Wee \ 2 29 —~ @ 08 =e au ad 3 eS 5902 > oe” °°) 5 go® - 8 9 oF ee > Las 2 9 3 ; —T rn as 2 oy. @-® QS ee? S82. see ono ee! ene 5 et eo 3 ee) OF 2. 5 I@P 10 ect wig.) 11 Ped. , ve eS? Gee) made ¢. 9992" 5, ¢@) a ose ~~ pve= and o gw Se Jee mae Ee ga 2? - S090 a BULLETIN 74 PL. 14 ee ee - ee oe = ey gee ev. 4eF 3 s2go22e= eee? se s332355 58S eGo eee. 2.999 3e 2. aes”, 2 eee ee - oa ase eet ge 6 12 *9~ see DETAILS OF STRUCTURE OF WEST INDIAN ECHINOIDS FOR EXPLANATION OF PLATE SEE PAGE 27. 1 - , i - 7 , iW 7 i iGreen ole vy ty a io ‘ r 7 4 i i the / oe i i i 1 : q / f yi tae i cl nis Mf = i i f a j . ve - fi Brin TAS bf i 15 BULLETIN 74 PL. = 2 w D =) = 4 at z 9 (= < z oe = DETAILS OF STRUCTURE OF WEST INDIAN ECHINOIDS FOR EXPLANATION OF PLATE SEE PAGE 27. U. S. NATIONAL MUSEUM BULLETIN 74 PL. DETAILS OF STRUCTURE OF WEST INDIAN ECHINOIDS FOR EXPLANATION OF PLATE SEE PAGE 27. 16 Geo tant cor BULLETIN 74 PL. 17 U. S. NATIONAL MUSEUM DETAILS OF STRUCTURE OF WEST INDIAN ECHINOIDS FOR EXPLANATION OF PLATE SEE PAGE 28. te 7 > ‘ ; 7 Ww iin ‘ - ee 7 yore 7 ¢ : / tt ; ae 2 _ : : “ used. 7 = ~~ a i INSTITUTI NC 14 “HANH 3 9088 0