394 H. L. Haiukins — Echinoidea Holectypoida. 



constrained to hope that the spirit herein manifested may inspire 

 an ever-growing ecclesia of individuals and institutions. A Museum 

 whose aim is to acquire and store away a miserly hoard of rarities 

 is in danger of becoming a mausoleum rather than a radiant centre 

 of vitality in research ; the individual who fails to welcome 

 discoveries, even when they might have been his own, is no apt 

 disciple, still less a true apostle, of the creed of science. 



Of the three specimens sent for study " 0.'' recens is now in ruins 

 (though even yet beautiful) ; 0. epigonus has acquired a coloration 

 unlike that secreted by any known Echinoid, and has unfortunately 

 lost its apical system ; while R. caribcearum has suffered removal of 

 many of its radioles. It is my earnest hope that the following notes 

 may atone in some measure for the damage done, and convey in the 

 most acceptable form my thanks for the prompt and almost reckless 

 generosity that enabled me to investigate material at once so precious 

 and so interesting. 



2. Apatopygus recens (Milne Edwards). 



This species was introduced by Milne Edwards in 1836 (Cuvier, 

 Regn. Anim. Zooph., pi. xiv, fig. 3), under the name Nucleolites 

 recens. At that date Nucleolites was a broad generic term covering 

 all Irregular Echinoids which have the periproct on the adapical 

 surface ; but in this particular case the close superficial similarity 

 between iV. recens and such fossil forms as N . scutatus made 

 application of the name unusually appropriate. D'Orbigny in 1854 

 (Rev. Mag. Zool.) automatically replaced Nucleolites by the pre- 

 Linnean Echinohrissus, but no reasoned attempt at better generic 

 precision was made until 1889, when Duncan (Journ. Linn. Soc, 

 vol.xxii) proposed 0%oj90f^^a as a subgenus, including the two recent 

 species of " Nucleolitidee " then known, recens and epigonus. In 1904 

 Hamann (Bronn's Thierreichs) raised Oligojwdia to generic rank, and 

 restricted it to 0. epigonus (Martens), which thereby became the 

 genotype. " Echinohrissus " recens was left in Nucleolites by Hamann, 

 but Clark (1917, Hawaiian and other Pacific Echini, p. 107), 

 believing recens and epigonus to be congeneric, and " quite 

 different from typical Nucleolites of Lamarck ", placed both under 

 Oligopodia. 



While concurring in Clark's opinion that both are incapable of 

 bearing the name Nucleolites, I am fully convinced that they are so 

 far from being congeneric that family, and indeed ordinal, distinctions 

 separate them. The reasons for this belief are subjoined, but the 

 systematic sequel can be indicated here. Nucleolites epigonus 

 Martens is the lecto-genotype (Hamann, 1904) of Oligopodia'Dnnca.n, 

 1889. Nucleolites recens M. Edwards is certainly not a Nucleolites 

 in the accepted sense of the term, and is even less akin to 0. ejngonus. 

 A new generic name is thus necessary for N. recens, unless that species 

 can be shown to belong to some other genus already diagnosed. 

 The latter condition does not obtain, so far as I can determine. 



