WEST INDIAN STAEFISHES 



173 



having only thirty marginal plates while hraziliensis has fifty, of 

 which those on the basal half of the ray bear two spines, but 

 these are shorter and less acute ; the former has, on the rays, pax- 

 illse with a small central spinule and six marginal ones, increas- 

 ing to eight on the disk, without change in character, while on 

 A. hrazUie^isis the radial paxillge have eight to twelve marginal 

 paxillas and often two or three central ones, and on the disk they 

 become crowded and granule-like, placed in concentric circles, 

 losing their stellate character, and forming groups of twenty or 

 more. Other differences are found in the adambulacral arma- 

 ture. 



In antilleims there are two rows of adambulacral spines each 

 with five or six, nearly equal, except the central one, which is a 

 little larger, while in hraziliensis there is an inner row with the 

 middle one compressed, curved, and a little larger, and just be- 

 hind this is one large, aboral, conical, pointed spine, having 

 alongside of it, adorally, two others, not more than half as large ; 

 and still further back some irregularly placed small spinules 

 (usually three or four). 



He states that the inferomarginal plates are covered in both 

 species with scales (flattened spinules), but in hraziliensis they 

 are more numerous, forming a uniform covering, but they are 

 only appressed, not imbricated. In antillensis these spinules are 

 more sparse and scattered. 



St. Thomas (Liitken). Guadeloupe (Perrier). 



AsTROPECTEN BRAZiLiENSis Miill. and Trosch. 



Astropecten hraziliensis Miill. and Trosch. Syst. Ast., p. 68, 1842. Duj. 

 et Hupe, op. cit., p. 415, 1862. Verrill, op. eit., 1864, p. 343. Perrier , 

 Eevision, op. cit., pp. 284, 288, 1876. E. Eathbim, op. eit., p. 150, 

 1879. Sladen, op. cit., 1889, pp. 194-198 (no description). 



A large characteristic specimen, from Rio de Janeiro (Coll. 

 C. F. Hartt, No. 5,204, Yale Mus.), has long, regularly tapered, 

 acute rays, wdth a narrow angulated border of marginal plates, 

 bearing proximally two rows of acute spines, the first on each 

 side decidedly longer and larger, marginal spines, of the lower 

 series, are long and acute, only one large one on a plate. 



The radii are 16™"^ and 96°^°^, ratio, 1:6; breadth of ray at 

 base, minus spines, IT"""", of paxillar area, at second pair of 



