224 DEVONIAN FAUNA. 



The occurrence, however, of a small detached plate (PI. XXX, fig. 2), sus- 

 piciously like the anal of Hexacrinus, makes it more likely that it was related to 

 that genus. But its style of ornament so closely resembles that of Arthracantha as 

 to suggest its identity with it. However, though the little tubercles which cover 

 the body-plates are so elongate that they may be probably regarded as spines, I 

 have been unable to trace their full length or their shape, and am not quite certain 

 that they are moveable. Hence, while this view may ultimately be found correct, 

 it certainly cannot as yet be asserted positively. It seems therefore best to retain 

 for the present Phillips's existing name for whatever it may be worth, rather 

 than to unite it with any genus from which it might again have to be separated. 



1. Adelocrinus hystrix, Phillips. Plate XXX, figs. 1 — 7 a. 



1841. Adelocrinus hystrix, Phillips. Pal. Foss., p. 30, pi. xvi, fig. 4,2 a, b. 



Description. — Dorsal cup large, deep, apparently obconical, composed of large 

 plates, which seem to be thin, covered with more or less numerous small elongate 

 tubercles or spines, and so closely united that signs of the sutures are rarely 

 discernible. Basal plates three, forming a shallow cone. Radials large, higher 

 than wide, subpentagonal, with a small excavation above. Anal plate ? narrow, 

 subquadrate. No other plates of the calix decipherable except a few small poly- 

 gonal plates (apparently of the dome), each of which bears a large rounded central 

 tubercle. Arms stout, probably not very long, about ten in number, and not 

 branching ; biserial, composed of rather high joints, and clothed with long stout 

 pinnules. 



Size. — A specimen of the cup with closed arms (perhaps not fully shown) is 

 about 40 mm long. 



Localities. — In the Museum of Practical Geology are a dorsal cup (Phillips's 

 type) from Brushford, a portion of another cup and some arms from Brauuton, 

 and two detached plates from Barnstaple. In the Barnstaple Athengeum are a 

 cup with arms (mould and reverse) and a plate of the calix with some arms from 

 Top Orchard, and portions of two other cups from Braunton. In the Porter 

 Collection are portions of three cups and two detached plates from Pilton. Frag- 

 ments of the dorsal cup do not appear to be rare. 



Remarks. — Although several specimens have been found, we are unable to 

 carry the description of this species very much further than where Phillips left it. 

 Repeated examination of the specimens has only resulted in showing indistinct 

 signs of the division of the lower part of the cup into three unequal plates ; and 

 the shape of the radials is only known from detached plates. The plates appear to 



