1888.] NATURAL SCIENCES OF PHILADELPHIA. 375 



ffliedert, nur an dev Basis scheint sich zuweilen ein Stiickchen 

 abzusetzeii. Die Hohe der Piimulae gleicht am breiteren Theil der 

 Hand der Dicke der Glieder." 



In the specimens which we have examined, the small alternating 

 plates which cover the ventral furrow are very plainly seen, but we 

 find no trace of the so-calJed "pinnules or saumpliittchen," which 

 were figured and described by Miiller and Angelin. It is evident 

 that the alternating inner plates, covering the ventral furrow, are 

 the "saumpldttchen" or covering pieces, and not the OM^er ones along 

 the lateral margins of the furrow, which, if they exist at all, proba- 

 bly are ad-ambulacral plates ; they cannot be pinnules in the ordi- 

 nary sense, for there are, according to Miiller, 3 to 4 to each arm- 

 joint. In one of our specimens (PI, XIX, figs, la, b), high up along 

 the arms, the covering plates are perfectly seen in place, and there 

 appear at their sides in some places, along the margin of the furrows, 

 what seem like serrated edges, several to a joint, and it may be that 

 Miiller and Angelin took these edges, which rise somewhat above 

 the level of the covering plates, for pinnules. If these are the struct- 

 ures figured by Miiller and Angelin (Bau. d. Echinod. PI. VIII, figs. 

 7 and 8 ; and Icon. Crin. Suec, PL XXV, figs. 19, 19a), then the 

 projecting parts are mostly broken away in our specimens, and in all 

 others we have seen. 



The arms of the species named by Miiller Anthocr'mus Loveni — 

 but which Angelin considered to be a synonym of Crotalocrinus 

 pulcher — were described by him as resembling the five leaves of a 

 flower, which when spread out would not connect, but when closed 

 were folded up, and overlapped each other. It is possible that this 

 is the case in that species, and in fact his cross-section ( Op. cit. PI. 

 VIII, fig. 4) clearly indicates it. But we have had before us three 

 specimens from Sweden and one from England, considered to be 

 C. rugosus, all having the arms completely spread, in some cases 

 bending downward, and in these the arms are certainly in lateral 

 contact, not only within the rays, but continuously all around. Also 

 the cross-section of the arms of this species, given in Murchison's 

 Siluria (3rd Ed. p. 247, fig. 4a), shows the continuous connection of 

 the arms, and how they fold in upon themselves when closed. The 

 specimen figured in PI. XX, fig. 4, which, in our opinion, is not G. 

 rugosus but an undescribed species, represents a form in which the 

 rays may have been disconnected as in C. pulcher. It differs widely 

 from Ijoth species in the first radials, which are excavated and have 



