SHALLOW-WATER STARFISHES 321 



Genus Astropectinides Verrill, nov. 

 Type, A. ntesacuttis (Sladen), as Astropecten. 



This genus is proposed for those species, usually referred to 

 Astropecten, which have a well developed triangular actinal area, 

 covered with two or more rows of interactinal plates parallel with 

 the adambulacrals and corresponding to them in radial length. The 

 proximal inferomarginal plates are correspondingly abbreviated, 

 not prolonged nearly or quite to the jaws, as in Astropecten. 

 The dorsal paxillae and upper marginal plates are as in Astropecten. 



Several species, described as Astropecten, besides the type, belong 

 to this genus. Among them are A. callistus (Fisher) and A. cteno- 

 phorus (Fisher), Hawaiian Islands. The genus is extralimital. 



The type, A. mesacutus Sladen (1883; and op. cit., 1889, p. 219, 

 pi. XXXIV, figs. 5, 6 ; pi. XXXVIII, figs. 7-9), has twenty to thirty spinu- 

 lose plates in each interradial area. It is from the Antarctic Ocean 

 and the South Atlantic, in 44 to 90 fathoms. 



Genus Bunodaster Verrill. 

 Plate Lxxxvi, figures i, 10; plate civ, figures i, 10; plate cv, figures i, la. 



Bunodaster Verrill, Amer. Naturalist, xliii, p. 554, fig. 4, September, 1909. 

 Fisher, op. cit, 1911a, p. 164; 1911b, p. 40. 



Superficial appearance much as in some dorsally unarmed species 

 of Astropecten, but with smaller marginal plates. 



Form stellate with elongated rays. Dorsal surface covered with 

 low, convex, somewhat hemispherical plates, which are of the nature 

 of parapaxillae, with enlarged, somewhat lobed or stellate concealed 

 bases, the lobes slender and articulated, with single papulae between 

 them. The surface of the outer boss, or raised part, is covered with 

 numerous small, slender, divergent, spinules, which form simple, deep 

 fascioles at the margins. 



Marginal plates not very thick, convex, all closely spinulose and 

 the lower ones spinose ; the upper ones are rather small, in the inter- 

 radial arcs, where the lower ones are not much prolonged adorally, 

 but end abruptly against a triangular area of fascioled and spinulose 

 actinal plates, which are flattish or convex and form rows parallel 

 with the adambulacrals, or three V-shaped rows with two odd inter- 

 radial plates in line. The adambulacral plates are the same in length 

 as the synactinals ; they have a horizontal furrow-group of three or 

 four spines and an actinal divergent group of similar ones. 



22 



