100 



THREE CRUISES OF THE " BLAKE. 



deep-water spatangoids is Hemiaster (Figs. 369, 370), a small 

 globular genus representing the earlier forms of spatangoids 



Pig. 369. — Hemiaster zonatus. |. Fig. 370. — Hemiaster expergitus. 5. (Lov^n.) 



characterized by a simple fasciole. Others belonging to the dis- 

 tinctly cretaceous family of Ananchytidse are the huge violet or 



Fig. 371. — Paleopneustes hystrix. §. 



deep claret-colored l Paleopneustes, characterized by their emi- 

 nently spatangoid mouthy by 

 their simple ambulacral system 

 and somewhat clypeastroid or 

 even echinidal spines, as in 

 Paleopneustes hystrix (Fig. 

 371), in which the spines re- 

 semble more those of a true 

 Echinus than a spatangoid. 



Other typical modern Ananchytidse are the West Indian Palaeo- 



brissus and Paheotropus. (Fig. 372.) 



1 The colors of the deep-sea echini alcohol in which they were placed. The 

 and other echinoderms seem to be spe- color of the littoral or shallow-water spe- 

 cially fugitive, and greatly discolored the cies is far more permanent. 



Fig. 372. — Palseotropus Josephinas. 



