118 NATURAL HISTORY BULLETIN 



Family Odontasterid^ Verrill. 



GnatJmsterince (pars) Perrier, Exp. Trav. et Talism., pp. 244, 251, 1894. 

 Odontasteridce Verrill, Eevision Genera and Species of Starfishes, p. 201, 

 1899. Fisher, op. eit., 19116, pp. 18, 153. Verrill, op. cit., 1914o, p. 

 302. 



Form either pentagonal or stellate with a broad disk. Mar- 

 ginal plates well-developed in both series. 



Jaws, each with a single, recurved, more or less hyaline median 

 spine, or with two such spines, side by side. In the latter case 

 one of these spines arises from near the apex of each oral plate. 

 Both conditions sometimes occur, abnormally, on the same speci- 

 men. 



An odd interradial marginal plate, above and below, on each 

 side. 



The marginal plates are covered either with spinules or gran- 

 ules; sometimes the upper ones are granulated and the lower 

 spinulose, like the corresponding disk-plates; they usually have 

 deep fasciolated sutures. 



Abactinal surface covered with more or less paxilliform plates, 

 parapaxillas or protopaxillge, with intervening large papular 

 pores on the radial areas. 



Interactinal plates angular, covered either with spines or 

 granules. Small simple pedicellari^e sometimes occur on the 

 interactinal or abactinal plates. They may have two, three, or 

 four papilliform blades. 



Adambulacral plates usually bear elongated spinules arranged 

 in three or four pairs of small transverse rows, generally only 

 two or three of the furrow-series are on each plate; sometimes 

 only one. Oral plates usually have elongated, acute marginal 

 and apical spines. They are sometimes closely united along the 

 median suture; in other cases (Odontaster) , they are separated 

 by a space covered only by membrane. 



Genus Odontaster Verrill. 



Odontaster Verrill, Amer. Journ. Science, xx, p. 402, 1880. Proc. U. S. 

 Nat. Mus., xvii, p. 262, 1894. Amer. Journ. Sci., xlix, p. 136, 1897. 



Gnathaster Sladen (pars), Voy. Challenger, vol. xxx, Asteroidea, p. 285, 

 1889. Perrier (pars), Exp. Trav. et Talism., p. 244, 1894. 



Odontaster Bell (pars), Proc. Zool. Soc, London, p. 260, 1893. Verrill, Re- 

 vision Genera and Species of Starfishes, p. 205, 1899. Fisher, op. cit., 

 19116, p. 154. Verrill, op. cit., 1914o, p. 303. 



Form stellate, with a vidde disk and short rays. 



