the Genera and Species of Starfish. 



281 



14. Tosia, Gray. 



The body formed of smooth and spineless ossicula, rather convex ; 

 the dorsal and ventral ossicula entire, without any impressed line, 

 subequal ; the marginal ossicula 2-rowed, with a small intermediate 

 one near each tip ; dorsal wart triangular. 



1 . Tosia anstralis. Body flat, with 5 slightly inflexed sides, the 

 central interradial dorsal ossicule largest, marginal 6 above and 

 below, with a small intermediate ossicule at the top of each side, 

 the lower gradually diminishing in size towards the top. 



Inhab. Swan River, Port Lincoln, and Van Diemen's Land. 



The granules between the ossicula are deficient in the dead and 

 washed specimens. There are 3 or 4 fossil species in the chalk. 



B. Echinasterina. The body discoidal, many-rayed, skeleton netted 

 with numerous elongated doubly mobile articulated spines on mammil- 

 lary tubercles ; dorsal warts numerous. 



15. Echinaster, Gray, Syn. Brit. Mus. 62. 

 Body star-like, granulated, depressed ; back rather convex, with 

 a circle of 10 — 15 conical dorsal warts! Ambulacral spines small, 

 placed in groups with a single continuous row of large slender 

 spines near them. The spines are very long and covered with a gra- 

 nular skin, and have generally a second articulation about one-third 

 the length from the base. 



1 . Echinaster Ellisii, Gray. Asterias Echinus, Solander and Ellis, 

 t. 60, 61, 62. Asterias Echinites, Lam. Dorsal warts 15 ; rays 11, 

 or 12; spines large, thick. 



Inhab. South America. H. Cuming, Esq. 



2. Echinaster Solaris. Asterias Solaris, Naturf 'orscher, xxviii. t. 1, 

 2. Rays 21 ; spines small ; dorsal warts 10. 



Inhab. . 



C. Cribellina. The body divided into cylindrical, elongated rays ; 

 dorsal wart single. 



a. Ambulacra with a single series of crowded filiform spines, some- 

 times united by a membrane at their base. 



f. Smooth, the rays netted, with mobile spines, with impressed dots 

 between the net work • dorsal wart convex, flat-topped, with a few ra- 

 diating grooves. 



* Spine single, large, on the junction of the ossicula, placed in equi- 

 distant series. 



16. Othilia, Gray. 



Skin smooth, polished ; ambulacra with two very close series of 

 filiform spines. 



1. Othilia spinosa. Asterias spinosa, Retz. Pentadactylosaster 

 spinosus, Linck, t. 4. f. 17. Asterias Echinophora, Lam. n. 25. not 

 Chiaje. Rays rather more than twice the length of the width of the 

 body. 



Inhab. North America, Virginia. 



