INVERTEBRATES. 199 



only seen in a lateral view. Third radials of the same size as 

 the second, from which they project out horizontally; strongly 

 curved upwards at the sides to connect with the small vault 

 pieces extending out over each ray; pentagonal in outline, as 

 seen from beneath, but having an additional angle on each side 

 not visible from below. 



Third primary radials supporting on each of their outer 

 sloping sides the divisions of the free rays, only the bases of 

 which we have seen attached to any of the specimens yet found, 

 though from the fact that the rays are free from the second 

 radials, and covered above by small vault pieces, it is evident 

 the species belongs to the group Steganocrinus. 



First anal plate near two-thirds as large as the first radials, 

 hexagonal in form, and supporting two smaller hexagonal 

 pieces in the next range. Above these there are three or four 

 others in the third range, but they belong, perhaps, nearly as 

 much to the vault as to the anal series, though they generally 

 connect with the second, and partly with the third, primary 

 radials on each side. 



First interradials about two-thirds as large as the first 

 radial pieces. They are a little longer than wide, regu- 

 larly hexagonal, and support on their superior sloping sides 

 two smaller pieces, which connect with the vault. 



The summit is depressed, and composed of small, somewhat 

 irregular pieces, which are more or less convex, while some of 

 those extending out over the free rays, between the body and 

 the bifurcation, rise into little conical nodes like those covering 

 the free divisions of the rays beyond. The subcentral proboscis 

 is slender, rises abruptly from the depressed vault, and is near 

 the base, composed of very prominent plates, which probably 

 form short spines farther up. The costse on the body plates 

 are mainly formed by the deep excavation of the corners of these 

 pieces, so as to leave a ridge extending from the middle to each 

 side of the same. Breadth of the body of the largest specimen, 



