96 Bihliographical Notices. 



Springer state, however, that the anal plate of Gnq^hiocrmiis * is 

 " placed between the radials, resting upon the truncate upper side 

 of the posterior basal." I cannot tmderstand why the American 

 species presenting this character were referred by them to Oraphio- 

 criniis rather than to Fhialocrmus, to which they are scarcely 

 inclined to aflford even a subgeneric rank. Messrs, Miller and 

 Gurley are fortunate in having found the " proboscis" so well pre- 

 served in Phialocrinns (^siocrinus) mcKjnificus and P. Harii, as it 

 has not hitherto been properly known in this genus ; and the bifur- 

 cating proboscis of the former species which is figured on their 

 plate ii. is an abnormality of much interest, 



A third equally doubtful genus is Delocrinus, M, & G., its typo 

 being Poteriocrhius liemisplicerieus, Shumard, while the authors also 

 refer to it Cyatliocrinus hiflexus, Geinitz, these being the same two 

 types which White united under the name Genocrinus. But " in 

 the ' North-American Geology and Palaeontology ' S. A, Miller con- 

 demned Ceriocrinus of White on the ground that the name was 

 preoccupied " by Koenig, Had he carried his literary researches a 

 little further, however, as others of his countrymen have done, he 

 ■would have learnt, firstly, that Oenociinus, Koenig, is only a 

 synonym of MiUericrinus, and, secondly, that it was never described 

 nor formally published, Ceriocrinus, White, is therefore a good 

 genus, as already recognized by Waehsmuth and Springer, and 

 Delocrinus, M. & G., only an unnecessary synonym f, 



Ahrotocrinus, as described by Miller and Gurley, is a somewhat 

 remarkable type. The calyx is bowl-shaped and dicyclic, with a 

 pentamerous base and apparently five radials, for there is no mention 

 of any other number. In line with the radials is a " first azygous 

 plate," of the same form as they have, which rests upon the upper 

 sloping sides of two basals, and further resembles the radials in being 

 " horizontally truncated the entire width above and having a gaping 

 sixture ; second azygous plate constricted in the middle and hori- 

 zontally truncated on top ; above this numerous plates form a single 

 longitudinal series until they graduate into the proboscis," We 

 are elsewhere told, however, that only ten of these plates are 

 visible " before the series is covered by the overlapping arm on the 

 right." 



The above description is a little difficult to follow ; for it is not 

 easy to understand how six equal and similar plates (five radials 

 and one azygous plate) can rest in the depressions formed by the 

 sloping upper sides of five contiguous basals. Three basals are 

 shown in the figure of the azygous side, and also portions of three 

 radials with the azygous plate, all four of which alternate regularly 

 with the basals. The opposite side of the cup must therefore be 

 remarkably unsymmetrical ; but not a word is said about this in the 



* '* Revision of the Palseocrinoidea, Part III.," Proc. Acad. Nat. Sci. 

 Philad. 1886, p. 176. 



t The above paragraph has of coui'se been written on the supposition 

 that a generic name which has once been proposed, though not adopted, 

 may be used again with a new signification. 



