26 ECHINOIDEA. I. 



canaUciUata\ among the deep-sea forms at all events one new species is found, and upon the whole 

 scarcely any genuine G. canaliciilata is found among them. 



In the typical G. caiialiadata the large globiferous pedicellarite do not differ much from those 

 of Goniocidaris hibaria, or still less from those of G. uiubraciiliiin\ they are somewhat narrower, and 

 the blade is a little curved inward below the rather large opening that reaches to the point; there is 

 no end-tooth (PL VIII. Figs. 8, 32). The small pedicellariae, on the other hand, are very different from 

 those of the genuine Gofiiocidaris-s-pecies , as there is no end-tooth (PI. \^III. Fig. 6). Spicules simple. 

 — The young are carried on the apical area. Cidaris> iiiitrix (Wyv. Thomson's type specimen 

 examined): the large pedicellariae (PL X. Figs. 3 — 4, 12, 14) very much resembling those of Stcreocidaris 

 grandis (Doderlein 116. PL VIII. 2); the small globiferous ones (PL X. Fig. 24) chiefly as in G.canali- 

 culata. — The young are carried round the mouth. 



The two species are most frequently easily distinguished as to their habitus. In C. mttrix 

 the apical area is densely set with rather long, club-shaped spines, between which large pedicellariae 

 are found abundantly. In G. canaliciilata the apical area is set with rather few and scattered, not club- 

 shaped spines some of which are quite small, so that the area looks rather naked; generall}- no pedi- 

 cellarise are found on the apical area. This difference, however, is not absolutely reliable, and without 

 the pedicellariae the two species are not always to be distinguished with certainty. 



It is evident that these two species cannot be referred to the genus Goniocidaris; especially 

 the small pedicellariae are different from those oi Goniocidaris, as they have no end-tooth. Doderlein 

 (116. p. 18) thinks G. canaliculata to be nearly allied to Dorocidaris; to be sure it occupies an extreme 

 position in the Borocidaris:>-gTOup, and perhaps it might also be regarded as the only representative 

 of a special grouj^. In many respects it recalls the ^£ucidarisi-group. Wirklich nahe Beziehungen 

 zu einer der bisher bekannten Arten von Cidariden bietet diese Form jedenfalls nicht dar^>. — As has 

 already been mentioned, the pedicellariae of C. iiutrix are very similar to those of Stcreocidaris grandis, 

 and these two species would seem to have to be referred to the genus Stcreocidaris; at all events 

 there seems to be no objection of consequence to their being referred to this gentis, and it might be 

 difficult to point out a character, which would necessitate the establishing .of a special genus for these 

 species. The simple spicules are in accordance with those of St. grandis (in the other Stcreocidaris- 

 species they are, as mentioned, large fenestrated plates). 



Of the species <i Goniocidaris -i vivipara and nienibranipora the former (according to Studer, 386) 

 is synonymous with G. canalicidata, which statement I am able to corroborate from the examination 

 of a specimen that our museum has received from the museum at Berlin. The other (also according 

 to examination of specimens from the museum at Berlin) is identical with <, Cidaris^ mitrix W. Th., as 

 has already been .supposed by Studer (385). As the paper by Wyv. Thomson (397) bears the date 

 of June i^' 1876, and that of Studer (384) the date of July 27"' 1876, the name of nutrix has the 

 priority. Now we meet here with a new difficulty. Studer .says of G. incmbranipora (384 p. 455): 

 Die jungen Cidaris bleiben auf dem Analfelde der Mutter bis zu ihrer voUigen Entwicklung, von den 

 obern Stachelreihen geschiitzt, die sich kreuzweise dariiber legens. According to this statement this 

 species would seem nevertheless to carr\- the young now arround the mouth, now on the apical area. 

 As this seems to me to be very improbable, I must suppose a mistake to have taken place, so that 



