278 Mr. J. E. Gray's Synopsis of 



1. Stellaster Childreni. Back convex, with 1 or 2 blunt tubercles 

 on the angles of the centre, arms three quarters the length of the 

 width of the body, narrow, attenuated to a blunt recurved tip. 

 Young, back without any tubercles. 



Inhab. China or Japan ? 



4. Comptonia, Gray. 

 Body depressed, spinose ? dorsal and oral disk covered with very 

 small flat plates, marginal ossicula large, without any mobile spines. 



1. Comptonia elegans, Gray. Fossil. Black Down. 



The fossil genus Cosl aster, Agassiz, from Maestricht, appears to be 

 most nearly allied to this genus, but the plates of the oral disk 

 (which alone are known) appear to be linear longitudinal. 



*** Body pentagonal, formed of variously shaped rather rough os- 

 sicula sunk into a naked skin, with a single series of spine-bearing tu- 

 bercles. 



5. Gymnasteria, Gray. 



1. Gymnasteria spinosa. Rays triangular, tapering, about one 

 quarter longer than the width of the body, with a dorsal series of 

 conical cylindrical tubercles. Young with a few spines on the mar- 

 gin and back of the arms. Allied to Porania. 



Inhab. Panama, fine sand, 16 fathoms. H. Cuming, Esq. 



2. Gymnasteria inermis. Rays rapidly tapering, convex above 

 without any spines. 



Inhab. Panama, fine sand, 10 fathoms. Half the size of the young, 

 spined specimens of the former species. 



b. The ambulacra with 2 series of larger spines near the edge; 

 body depressed ; back flat. 



* The ossicula granulated, sunk in the skin, often spine-bearing. 



6. Paulia, Gray. 



Body 5 -rayed, formed of flat granulated spine-bearing irregular 

 ossicula on the disk and margin without any 2-lipped pores. 



Paulia horrida. Chestnut brown ; spines acute. 



Var. Smaller, arms as long as the width of the body, rather ta- 

 pering, spines smaller, blunt, rounded at the tip ; back more closely 

 granulated. 



Inhab. Punta Santa Elena. Rocky ground, 12 to 18 fathoms. 

 H. Cuming. Esq. 



7. Rand asia, Gray. 



Body pentagonal, with a tubercular skin above, and large granu- 

 lar plates beneath and on the margin, without any 2-lipped slits, but 

 with one or two small pores near the oral angle beneath, where the 

 tubercles are rubbed off. Allied to Culcita. 



1. Randasia Luzonica. Thick, brown, the tubercles of the under 

 side unequal, the larger ones flat-topped : sides straight. 



Inhab. Island of Lucon, in the Port of Sual. H. Cuming, Esq. 



