EOHINODERMATA. 153 



CRINOIDEA. 



In the preparation of this portion of my Report I have had the 

 very considerable advantage of the kindness of Mr. P. Herbert Car- 

 penter, whose work on this group is so well known to, and so highly 

 appreciated by, his fellow-workers. .Mr. Carpenter has not only 

 been good enough to favour me with his opinion on many of the 

 species and specimens in the present collection, but, at what must 

 have been considerable trouble to himself, he copied out for me 

 the notes that he had been able to make at various times and 

 places on the " type specimens " of the species named by the illus- 

 trious founder of the system of this group ; thanks to this act of 

 kindness, I have probably escaped from some of the numerous pitfalls 

 which, with the advance of our knowledge, now surround the student 

 who applies himself to Johannes Midler's descriptions of the differ- 

 ent species. As Mr. Carpenter will, in the progress of time, publish 

 his studies on these Miillerian types, I have thought it proper on 

 this occasion to do little more than merely note the presence of such 

 forms in this collection. 



The proportion of undescribed to described species is no doubt 

 appalling ; but on making a careful estimate I do not find it to be 

 practically greater than in the case of my predecessors. In a Note 

 which I communicated to the Zoological Society in May 1882 I gave 

 a list of all the described species, which was very nearly complete : 

 therein were enumerated 37 Antedons and 21 Actinometrce. Of 

 these, 7 Antedons aud 4 Actinometrce were first described in 1881, 

 from the collection of the Leyden Museum, by Mr. Carpenter. In 

 that paper the percentages of new to all the known species were 

 respectively 23 and 23 ; the percentages to new species in the col- 

 lection respectively 70 and 40. 



As there are here described 12 new species of Antedon, my per- 

 centage to the 37 described forms is 32*5, to all the species men- 

 tioned in this Report it is 75 ; on the other hand, there are some 5 

 new species of Actinometra, giving a percentage of 23 - 5 to all the 

 described forms, and of 38 to those enumerated in the accompanying 

 list. 



Against this higher proportion we must, however, set off the fact 

 that five of the earlier species had been described by Midler from 

 the specimens in the Leyden Museum. 



. But the whole story has not yet been told : without, of course, 

 wanting in any way to tie Mr. Carpenter down to details, I may add 

 that his examination of the 'Alert' collection was made after he had 

 examined the collection of Crinoids brought together by the officers 

 of H.M.S. 'Challenger,' and entrusted to him for description. Only 

 a single form among the " new species " in the present collection 

 has been detected by Mr. Carpenter to be one of the treasures which 

 he has described, but whose description he has not yet published ; 



