1886.] NATURAL SCIENCES OP PHILADELPHIA. 149 



c. Cyathoerinites. 

 CYATHOCRINirS J. S. Miller, Rev. I, p. 79. 



Through the kindness of Prof. Whiteaves we had an oppor- 

 tunity to examine E. Billings' tj'^pe specimens of Palseocrinua in 

 the Canada Surve}^ Museum. The specimen of P. striatus, upon 

 which the genus was proposed, is very imperfect, and may be a 

 Garabocrinus, Dendrocrinus, or a new genus. The construction at 

 the ventral side, to which E. Billings attached so much weight, is 

 that of the C_yathocrinidj3e generally. The^' nearly all have ventrally 

 five interradial plates resting against the radials, and alternate 

 rows of covering plates. Heretofore we have placed Palseocrinus 

 angulatus Billings under Cyathocrinus, but we satisfied ourselves 

 from the original specimen that it is a true Dendrocrinus. Gyatho- 

 crinus fasciatus Hall, is a synonym of Macrostylocrinus Meeki ; 

 Gyathocrinushamiltonen.ns Worthen, a s^monymof Gyathocrinus 

 parvibrachiatus Hall. G. nucleus and C. polyxo Hall are now 

 referred by us to Homocr inus ; G. waldronensis to Macrostylo- 

 crinus. Gyathocrinus graphicus Blgshy (not Hall) is Platycrinus 

 graphicus. 



1879. (?) Gyathocrinus Harris! S. A. Miller, Journ. Cincin. Soc. Nat. Hist., vol. ii, 

 PL 13, fig. 2. Keokuk liinest. Crawfordsville, Ind. 



We leave this species for the present under Gyathocrinus, al- 

 though aware that it represents a very different generic form. In 

 some respects the species closely resembles Belemnocrinus 

 Jlorifer, and might almost be considered identical with it, if the 

 column did not indicate a dicyclic base. The column of both 

 species is sharply pentagonal, and beautifully fringed with whorls 

 of cirrhi, but while in Belemnocrinus Jiorifer the outer anoles of 

 the column are directed radially, the cirrhi interradially, the very 

 opposite is the case in Gyathocrinus (?) Harrisi. Neither can 

 the species be referred to our genus Atelestocrinus, as this is 

 remarkable for its large underbasals, nor in fact to any other 

 known to us, and we should make it the tj'pe of a new genus if 

 the two specimens which we examined were more perfect. The 

 specimen in the collection of Mr. Harris, which he had the kind- 

 ness to send us for examination, leaves us in doubt whether the 

 so-called azygous plate of Miller does not represent the anterior 

 radial. Among the Fistulata the anterior ray very frequently 

 supports a single arm, which either remains simple or branches 



