26 ECHINOIDEA. I. 



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

 scarcely any genuine G. canalictilata is found among them. 



In the typical G. canaliculata the large globiferous pedicellarise do not differ much from those 

 of Goniocidaris tubaria, or still less from those of G. timbraculum; 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 (PI. VIII. Figs. 8, 32). The small pedicellarise, on the other hand, are very different from 

 those of the genuine Goniocidaris-species , as there is no end-tooth (PI. VIII. Fig. 6). Spicules simple. 

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

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

 grandis (Doderlein 116. PI. VIII. 2); the small globiferous ones (PI. 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. nutrix 

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

 are found abundantly. In G. canaliculata 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; generally no pedi- 

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

 the pedicellarise 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 pedicellarise are different from those of 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 D0roctdaris-group, and perhaps it might also be regarded as the only representative 

 of a special group. In many respects it recalls the jEucidarts-group. Wirklich nahe Beziehungen 

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

 already been mentioned, the pedicellarise of C. nutrix are very similar to those of Stereocidaris grandis, 

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

 there seems to be no objection of consequence to their being referred to this genus, 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 Stereocidaris- 

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



Of the species Goniocidaris^ vivipara and membranipora the former (according to Studer, 386) 

 is synonymous with G. canaliculata, 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* nutrix W. Th., as 

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

 of June I st 1876, and that of Studer (384) the date of July 27 th 1876, the name of nutrix has the 

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

 Die jungen Cidaris bleiben auf dem Aualfelde der Mutter bis zu ihrer volligen Entwicklung, von den 

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

 species would seem nevertheless to carry 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 



