ECHINODERMA. 5 



III. ECHINOIDEA. 



CiDARIDAE. 



CiDARIS OANALICULATA. 



Temnocidaris canaliculata, A. Agassiz, Bull. M.C.Z. i. (1863), p. 18. 



Goniocidaris canaliculata, id. Eev. Echin. (1872), p. 131 ; Wyv. Thomson, Journ. Linn. Soc. xiii. (1876), 



p. 65 ; Loven, Bih. Svensk. Akad. Hdlg. xiii. iv., 1. p. 5 ; Agass., Mem. M.O.Z. xxxi. (1904), p. 4. 

 Gidaris {Borocidaris) canaliculata, Doderlein, Jap. Seeigel, i. (1887), p. 16. 



Gidaris canaliculata, Meissner, Ergebn. Hamb. Magalh. Sammelreise, v. (1900), ]., p. 3 iUgue citata. 

 Stereocidaris canaliculata, Mortensen, Ingolf Echinoid. (1903), p. 29. 



I have given the name of C. canaliculata to a number of specimens of an 

 Echinoid, which were mainly collected at a depth of 100 fms., but I must own to 

 grave doubts as to the correctness of the name. It seems to have escaped notice 

 that this consensu omnium (with the exception of Dr. Mortensen*) circumpolar 

 Antarctic form was first described from the " Caroline Islands," which Caroline Islands 

 we surmise to be those in the Pacific, as in the Revision of the Echini we find 

 " Caroline and Sandwich Islands " ; elsewhere, Zanzibar and the Navigator Islands are 

 given as habitats, "if the localities are to be trusted"; that is to say, the species 

 was founded on specimens said to be found within the tropics. 



I am not going to join those who claim that forms must differ specifically, either 

 because they are found at different spots or different depths ; but, as I showed many 

 years ago, there is a distinct intertropical fauna in the Great Ocean,f and the fact, if 

 fact it be, that a member of that fauna is also a circumpolar Antarctic form ought to 

 rest on the firmest possible basis. Unfortunately, the National Collection has no 

 examples from any station further north than Tasmania. 



Again, the original diagnosis, based on the Caroline specimen or specimens, is too 

 short for a form which every student who has examined it, except Dr. Mortensen, allows to 

 be eminently variable ; with the exception of Prof. Doderlein, none of these students has 

 given a serious diagnosis of the species, and even his is not altogether what one wants. 



Yet another difficulty remains to be mentioned ; it is generally agreed that 

 C. nutrix J and C. vivipara are synonyms of C. canaliculata ; in other words, the form 

 has a marsupial habit, but I cannot detect signs of it in the specimens before me ; 

 it may be, of course, as it curiously is in the case of ffemiaster cavernosus, that this 

 collection consists of males only ; but Mr. Hodgson tells me that he observed no signs 

 of viviparous habit ; our experience, in fact, is the same as that of the late Felix 

 Bernard §: " Quoique G. canaliculata soit signal^ comme vivipare, je n'ai pas constate 

 aucun jeune sur le corps des adultes." 



* Op. cit., p. 27. 



t For some modification of this doctrine, see Prof. Koehler in "Die Fauna Sudwest-Australiens " I. iv. 

 (1907), p. 242. 



X Prof. Lyman Clark doubts this (see f.-n. next page) ; of C. vivipa/ra of Studer he makes no mention. 

 § Bull. Mus. Paris, i. (1895), p. 272. 



VOL. IV. Q 



