104 Dr. P. H. Carpenter on some Points in 



this appears to be the standard set up by Professor Perrier 

 for those who have large zoological collections committed to 

 their charge for examination and description within a limited 

 time. 



Under these circumstances, therefore, one might expect that 

 the Report by Professor Perrier* upon the fifty-four species of 

 Asterids which were obtained by the ' Blake ' in the Carib- 

 bean Sea, a collection second only in importance to that made 

 by the ' Challenger,' would be a model of its kind. 



In the absence both of an index and of a table of contents, 

 one has some difficulty in making out what is contained in 

 this memoir of l-'.O pages. Of the ten plates which accompany 

 it, only one is devoted to any other part of the subject than 

 the external appearance of the new species established by 

 Prof. Perrier. At the foot of this plate, which is almost 

 entirely occupied by figures of pedicellaria3 and spines, there 

 is the extraordinary legend " Organisation des Hymens 

 discus " ; and the reader has to turn back to the explanation 

 of the plates in order to learn that the name of Prof. Perrier's 

 new genus is in reality Hymenodiscus. Not one of the re- 

 maining nine plates contains any figures illustrating the 

 organogeny of the starfish, a subject upon which we are still 

 much in want of information, despite the admirable researches 

 of Ludwigt upon Asterina gihhosa. Neither is there any 

 section of the text devoted to this question, while the amount 

 of physiological and anatomical information which the report 

 contains is meagre in the extreme. 



Three years ago Professor Perrier published a short note \ 

 in the ' Comptes Rendus ' to call in question the correctness 

 of some of Ludwig's observations on Asterid morphology ; and 

 many Echinoderm students had hoped that he would take the 

 opportunity afforded by the material of the ' Blake ' Starfishes 

 to substantiate his charges respecting the accuracy of Ludwig's 

 work on the group. But the whole question is completely 

 ignored, with the exception of one or two references to the 

 position of the stone-canal, and there is not a word about the 

 organogeny of the Starfish type, a subject which, according to 



* " Memoire sur les Etoiles de Mer recueillies dans la Mer des Antilles 

 et le Golfe du Mexique durant les Expeditions de dragage faites sous la 

 direction de M. Alexandre Agassiz," Nouvelles Archives du Museum 

 d'Histoire Naturelle, 2« serie, tome vi. 1884, pp. 127-276, pis. 1-10 

 (1884). 



t " Entwicklungsgescbiclite A.er Asterina gibbosa, Forbes," Zeitschr. f. 

 wiss. Zool. Bd. xxxvii. 1882, pp. 1-98, Taf. i.-viii. 



\ Perrier and Poirier, " Sur I'Appareil circulatoire des Etoiles de Mer,'' 

 Comptes Rendus, t. xciv. 1882, pp. 658-660. 



