WEST INDIAN STARFISHES 119 



A single, odd, hyaline, recurved movable spine is on the apex 

 of each jaw. The oral plates axe large, partly separated by an 

 open fusiform space covered by membrane. Abactinal surface 

 covered with elevated, convex or clavate paxilliform plates, or 

 parapaxillas, which usually bear clusters of elongated spinules, 

 like true paxillag ; their bases are stellate. The upper marginal 

 plates are usually finely spinulated. 



The adambulacral plates usually bear several rows of spines, 

 usually three or four in the furrow-series, rarely but two. 



The odd interradial marginal plate is usually triangular or 

 wedge-shaped. Simple pedicellariee occur rarely. 



The radial abactinal plates form more or less evident obliquely 

 transverse rows and some extend nearly or quite to the apical 

 plate. 



Papular pores are generally large and placed singly in the 

 angles around the radial parapaxillae. 



The inferomarginal plates and interactinal plates are covered 

 with acute, more or less elongated spinules. 



Odontaster hispidus Verrill. 



Odontaster hispidns Verrill, Amer. Journ. Sci., vol. xx, p. 402, 1880. Proc. 

 U. S. Nat. Mus,, vol. xvii, p. 263, 1894. Amer. Journ. Sci., vol. xlix, 

 p. 136, 1895; Verrill, Eevision Genera and Species of Starfishes, p. 

 205, pi. xxix, figs. 8, 8a, 1899. 



Plate xiii; figure 6. 



Form depressed, stellate, with a rather broad disk. Radii 

 vary^ in proportion from 1 :2 to 1 :3. A large example has the 

 greater radius 55™™; lesser, 16™™. 



The marginal plates are only moderately developed and do not 

 encroach much on the disk, either above or below. In large 

 examples there are about 37 to 39 on a side, in each series. They 

 are convex and separated by wide and rather deep sutural 

 grooves. The upper and lower nearly coincide. The upper ones 

 are squarish, with rounded angles ; the lower ones, along the disk 

 margin, are higher than long. The odd interradial one is some- 

 what wedge-shaped, and only a little smaller than those adjacent 

 to it. 



The abactinal plates are round at top, convex, well separated ; 

 those of the radial areas and center of the disk are elevated, with 

 a somewhat capitate top, covered by a dense cluster of slender, 



