WEST INDIAN STARFISHES 



175 



rather slender spines, slightly flattened; the central one longer 

 and somewhat compressed. The second series consists of a very 

 large and stout, tapered, obtusely pointed aboral spine, with one 

 or two much smaller, slender, spatulate ones on the adoral side ; 

 when there are two, one stands behind the other. They are 

 scarcely half as long as the large one. The outer row is pretty 

 regular and formed by three to five small spatulate spines. 



The dorsal paxillar area is rather wide, nearly even, densely 

 covered with small coronate paxillae whose outlines are mostly 

 easily visible. On the rays the paxillas form irregular trans- 

 verse rows, except along the median band, where they are larger 

 and crowded. The smaller ones on the rays have eight to ten 

 marginal spinules around one or two granule-like, larger central 

 ones. 



The larger ones may have twelve to sixteen marginal spinules 

 and three to six in the middle. On the disk most of the paxillae 

 are larger ; they may have sixteen to twenty-four small marginal 

 spinules surrounding a central rosette of slightly larger capitate 

 ones, consisting of six to nine, in a circle, surrounding one or 

 two in the center. The spinules are all short and capitate or 

 clavate. 



The madreporic plate is large and plainly visible, surrounded 

 by a circle of the larger regular paxillae, with only one row of 

 them separating it from the marginal plate. 



The ocular plate is unusually small and narrow, bilobed by a 

 deep median groove. According to Perrier (op. cit., 1876, p. 

 284) the dorsal radial paxillae have eight to twelve marginal 

 stellate spinules with two or three central ones, but on the disk 

 the spinules become more numerous and crowded, about twenty 

 on a plate arranged in circles, and so reduced in length as to 

 appear like granules, showing only their hemispherical ends, due 

 to the crowding. 



The superomarginal plates bear two rather short spines on the 

 proximal half at least. These spines may be 1™°^ high. 



The inferomarginals are almost entirely covered beneath with 

 small flattened or scale-like, appressed spinules, which are not 

 imbricated ; near the transverse sutures these scale like spinules 

 give place to four or five elongated, flattened, acute spines, in- 

 creasing toward the upper margin, near which there is between 



