1918 Bush: on Echinoderms 29 



Papular areas small; papulae few. Dorsal ossicles thick, rounded, 

 elliptical or lunate, covered with clustered spinules ; densely crowded, 

 varying much in size and form; marginal rows of spines divergent at base; 

 jjeractinal row distinct, regular, parallel to marginals; peractinal plates 

 smallest of the 3 groups ; lower marginals largest, all spinulose ; adambu- 

 lacral ossicles bearing 2 or 3 transverse groups of graded spines ; these 

 spines largest toward groove, 1 short one in groove ; adorals short. Color 

 of starfish usually deep orange. — Numerous, in deep water and along tide 

 line. 



la. Henricia leviuscula lunula Verrill. 



Similar to the typical //. leviuscula. Marginals and interactinals form 

 o regular rows of plates that are longer and wider than the rest. The dis- 

 tinguishing characters are these: Dorsal ossicles reniform or curved, or 

 crescent-shaped with blunt cusps, partially enclosing a papular pore on 

 the concave side. — Numerous, in deep water. 



Family SOLASTERIDAE 



KEY TO GENERA 



A. Dorsal spines short, blunt, equal in length ; ossicles bearing spines 

 crowded. solaster (p. 29) 



AA. Dorsal spines long, slender, unequal in length ; ossicles bearing spines 

 scattered. crossaster (p. 30) 



Genus Solaster 



Rays 7 to 13; disk broad. Dorsal ossicles small, lobed, usually reticu- 

 lated on disk and rays ; bearing stellate clusters of slender movable spinules 

 which are webbed together; up})cr marginal plates small, like the dorsals; 

 lower marginals large, elevated, transversely oblong, forming evident rows ; 

 adambulacral plates with from 2 to 4 webbed groove spines, with a trans- 

 verse row of longer webbed spines. Interradial areas small. Papulae 

 numerous on dorsal surface, single or grouped. 



key to species 



A. Rays 9 or 10. 



B. Rays short, flattened. 1. S. galaAdes 



BB. Rays long, rounded. 2. S. stimpsoni 



AA. Rays 12 or 13. S. S. daicsoiii 



1. Solaster galaxides Verrill. 



Rays 9 or 10. ratlur sliort. taj)ered rapidly; disk broad. Dorsal 

 ossicles small, closely united; pai)ular areas small; dorsal surface covered 

 with small crowded flat-toj)]jed pseudopaxillae with 12 to 15 spinules each; 

 marginal plates ])res( nt ; lower marginal plates elongated transversely, with 

 many spines; peractinal row one-tlnrd of jiroximal ray; interradial s]iaces 



