VILL. Cyathocrinus. 203 
diagnosis of the genus (p. 85) is as follows :— A Crinoidal 
animal, with a round or pentagonal column formed of nume- 
rous joints, having side arms proceeding irregularly from it. 
On the summit adheres a saucer-shaped pelvis of five pieces, 
on which are placed in successive series, five costal plates, five 
scapule, and an intervening plate. From each scapula 
proceeds one arm having two hands.” The generic diagram 
facing p. 85 shows five pentagonal infrabasals, five basals, of 
which four are hexagonal (or pentagonal according to the 
angles formed by the upper sides of the infrabasals) and the 
fifth heptagonal (or hexagonal), five radials with a deep notch 
and an articular facet about one third the width of the plate, 
and a hexagonal anal z in line with the radials. The figures 
of C. planus—1, 2, 3, 4, 5, 6, 7, 8, 9, 29, 830—show that this 
diagram was taken from that species, and bear out the 
diagnosis so far as the cup is concerned. Fig. 1, however, 
shows dichotomous pinnulate arms, and we know of no genus 
with arms of this character that has a dorsal cup like that 
shown in the diagram. ‘The Austins’ explanation of this was 
a probable one. They said (Monogr. Rec. & Foss. Crinoidea, 
p- 61), “ Miller’s principal figure of this species cannot be 
depended on, as he appears to have taken the rays of the 
Taxocrinus longidactylus and placed them on the body of the 
C. planus.” On this Wachsmuth and Springer remarked 
(Revision, I. 81, footnote 2), ‘‘ In supposing these to be the 
arms of Zaxocrinus, Austin is certainly mistaken.” Austin, 
however, applied the name Yaxocrinus longidactylus to a 
specimen from the Carboniferous Limestone, near Walton 
Castle in Clevedon Bay, of which a figure had been published 
by George Cumberland *. This very figure was referred by 
Miller (p. 86) to C. planus, and it is quite likely that the 
arms of his own fig. 1 were suggested by it. As a matter of 
fact there can be little doubt that Cumberland’s figure repre- 
sents a Scaphiocrinus with two primibrachs, although the 
pinnules are merely indicated in his drawing by rough 
shading. ‘lhe same specimen was figured by Austin, pl. xi. 
fig. 3a, under the name Potertocrinus longidactylus (p. 88), 
thus showing that the name Yawocrinus was inserted by 
mistake on p. 61. Mr. W. P. Sladen, in his revision of the 
“Genus Potertocrinus and allied forms ”’ , left this species out 
in the cold; but Messrs. Wachsmuth and Springer referred it 
* “ Description of some new Fossil Encrini and Pentacrini, lately dis- 
covered in the neighbourhood of Bristol,” Trans. Geol. Soc. 1st ser, vol. v. 
part 1, pp. 87-94, with pls. 11.-v.: London, 1819, See pl. iii. fig. 1. 
t Proc. West Riding Yorksh. Geol. and Polyt. Soc. vol. vi. (n. s., 
vol. i.) part iv. pp. 242-253, pl. x. (1877), 1878, 
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