TEMNOTREMA. 317 



TEMNOTREMA. 



A. Agassiz, 1863. Proc. Acad. Nat. Sci. Philadelphia, p. 358. 



Type-species, Temnotrema sculpta A. Agassiz, 1863, 1. c. 



(= Pleurechinus A. Agassiz, 1872, and later writers; non Pleurechinus L. Agassiz, 1841, Int. Mon. 



Scut., p. 7.) 



The genus Pleurechinus was established by L. Agassiz in 1841 (1. c.) and he 

 definitely selected Cidaris bothryoides Leske as the type-species (1841, Int. 

 Valentin's Anat. Genre Echinus, p. viii). In 1846 however he abandoned the 

 generic name and placed bothryoides in Temnopleurus. Although he says his 

 Temnopleurus bothryoides is equivalent to Leske's Cidaris bothryoides, it is clear 

 that such is not the case for his diagnosis does not apply at all to the species 

 figured by Klein and described by Leske. Fortunately Agassiz labelled as 

 bothryoides a fine bare test in the Michelin collection in Paris, to which his 

 diagnosis of Temnopleurus bothryoides does apply, and this was taken by A. 

 Agassiz in the "Revision" and by later writers as the type-specimen of Pleurechi- 

 nus bothryoides. In the "Revision" however, it is distinctly stated that this 

 specimen is entirely different from Cidaris bothryoides Leske, which is perhaps 

 a Microcyphus. Clearly then the Paris specimen cannot be the type of Pleur- 



^ 



echinus bothryoides, which according to Agassiz in 1841, was nothing more nor 

 less than Leske's species. What names then should be applied to the Paris 

 specimen and to the genus to which it belongs? Since it is not labelled "Cidaris 

 bothryoides Leske," there seems to be no reason why its name may not stand as 

 Temnopleurus bothryoides Agassiz, but of course, it cannot be the type of Pleur- 

 echinus which is the entirely different Cidaris bothryoides Leske. Since this 

 latter is with little doubt, quite unrecognizable (for even if it is a Microcyphus 

 the species is not determinable with certainty), the name Pleurechinus must be 

 abandoned, and the group which has borne it for so many years must take 

 another. Fortunately such a name already exists, having been proposed in 

 1863 by A. Agassiz, for a small sea-urchin from Japan, Temnotrema sculpta. 

 Later the specimen was believed to be a young Temnopleurus Hardwickii and 

 in the "Revision" Temnotrema sculpta is placed in the synonymy of the Temno- 

 pleurus. The type-specimen of Temnotrema sculpta (PI. 112, figs. /, 2) is in 

 the M. C. Z. collection and comparison with other Japanese material shows that 

 it is identical with the species described by Mortensen (1904, Dan. Exp. Siam: 

 Ech., p. 84) as Pleurechinus variegatus. As a specimen of variegatus was re- 

 ceived from Dr. Mortensen himself, there can be no doubt of the identification. 



