SHALLOW-WATER STARFISHES 3I7 



Genus Astropecten Gray (emended). 



Asiropecten (pars) Gray, Ann. and Mag. Nat. Hist., vii, p. i8o, 1840; Sys- 

 tem, p. 3, 1866. Miiller and Troschel, Syst. Aster., p. 67, 1842. SladetJ. 

 op. cit., 1889, p. 193. Fisher, op. cit., 191 16, p. 55. 



Stetlaria Nardo, Oken's Isis, p. 716, 1834 (non Miiller, Mollusca, 1832). 



Asterias L. Ag.\ssiz, Prod., p. 191, 1835. 



Rays more or less elongated, subacute, flat above, with true abac- 

 tinal, stellate paxillse, and stout, fasciolated marginal plates. The 

 upper marginals are convex, encroaching more or less on the upper 

 side of the disk, usually spinulose, sometimes almost granulose, and 

 often with one or two superior spines or tubercles. Lower marginals 

 spinulose and spinose, prolonged actinally, most of them reaching 

 the adambulacral plates ; but one or two interradial pairs may not 

 reach the adambulacral plates, and in that case one or two pairs of 

 small adoral interactinal ossicles may intervene, but these do not form 

 regular rows, nor an important triangular area. The species having 

 an important group of actinal plates are here separated as a genus, 

 Astropectinides. The lower marginals are closely spinulose and 

 fasciolated laterally. Adambulacral plates about equal in number 

 to lower marginals, the inner end angular. They have a horizontal 

 group of about three furrow-spines and a divergent stellate group 

 on the actinal side, often with the central spine enlarged. The 

 papute stand singly around the dorsal paxilke, generally absent along 

 the median line. Dorsal pore usually lacking, sometimes present. 

 Superambulacral plates well developed. Pedicellariae generally 

 lacking. 



ASTROPECTEN SIDEREALIS Verrill. .sp. nov. 



Plate L, figure 6 (details). 



Astropecten armaius FiSHER (non Gray), op. cit., 1911&, p. S6, pi. v, figs, i, 2; 

 pi. vn, figs. 3, 6 ; pi. L, fig. 4 ; pl- u. fig- 3- 



A variable species. The type has the following characters : Disk 

 of moderate size, thick; rays five, rapidly tapered, acute. Radii, 

 14 mm. and 58 mm. ; ratio, i : 4.15. 



The upper marginal plates are short, convex, prominent, their 

 upper ends rising above the level of the abactinal paxillae. They are 

 separated by rather wide and deep fasciolated grooves ; those in the 

 interradial angles are externally wedge-shaped, with the sutures 

 vertical, but distally the sutures become oblique and the plates 

 scarcely wider than long. Most of their outer surface is closely 

 covered with small, roinided or hexagonal granules, which grade 



