WEST INDIAN STARFISHES 183 



convex. Their outer surface is well covered with small, un- 

 equal, acute spines, which form about three or four irregular 

 rows, transverse to the rays. These spines, at the middle of 

 the row, may be as long as the radial breadth of the plate. There 

 may be six to eight or more in a row. The upper ones, two or 

 three in number, are larger and longer and stand at the base of 

 the two large spines that stand on the superior margin of the 

 plate, side by side. These are a little curved, often somewhat 

 flattened, tapered and acute, those on about the eighth to tenth 

 plates are somewhat the larger. In length they about equal the 

 radial breadth of two plates, and are more than twice as long 

 as the longest upper marginal spines. 



Interactinal plates are very small and few, in the interradial 

 areas. They are spinulated and some of them usually bear 

 papilliform pedicellariae. 



The adambulacral plates proximally have a marginal row of 

 three slender acute spines, of which the median is a little the 

 longest and largest, and occupies the apex of the angular mar- 

 gin ; it is a little curved and usually compressed. On the actinal 

 surface of the larger subproximal plates, there are usually 

 four or five similar, slender spines (three or four more distally). 

 These may stand nearly in two rows, but normally three or four 

 stand on the border of the plate and one, slightly larger, stands 

 nearer the center, so that, as preserved, they often form a sub- 

 stellate group ; but more often they appear irregular and crossed, 

 due to contraction or pressure. Sometimes four or more of these 

 spinules converge and form a fasciculate pedicellaria, especially 

 on the jaws, but these are often absent or very few. 



The madreporic plates is small and nearly concealed by the 

 paxillae. A minute dorsal pore appears to be present at the 

 summit of the central cone. 



It was taken by the Bahama Expedition at station 64, off 

 American Shoal, Fla., in 110 fathoms (five specimens, including 

 the type) ; stations 56, 57, 58, Pourtales Plateau, in 200 to 225 

 fathoms (several, one specimen is rather thicker and more spin- 

 ose than the type.) Station 28, off Florida, 116 fathoms, one 

 young. It was taken by the Albatross, at station 2,418, in 90 

 fathoms, off Georgia, N. lat. 33° 20' (No. 18,350). 



This species appears to be closely allied to A. alligator Per- 



