STARFISHES OF THE PHILIPPINE SEAS. 473 



6^ Adradial plates inconspicuous, largely obscured by tbe large carinals; 

 R=16 to 17 r ; papular pores very small. 

 c\ Carinals hexagonal ; 2 or 3 lateral rows of spines ; 1 transverse series 

 of subambulacral spines on both kinds of plates ; rays hemicylindri- 



cal ; tube feet quadriserial barathri Alcock. 



c*. Carinals squarish ; .5 lateral rows of plates witli central spines ; 2 

 transverse series of subambulacral spines on both sorts of plates; 

 rays strongly carinated ; tube feet biserial microporus Fisher. 



ZOROASTER OPHIACTIS Fisher. 



Plate 135, figs. 2, 2a-'b ; plate 13G, fig. 1 ; plate 139, fig. 3. 

 Zoroaster ophiactis Fisher, 1916&, p. 29. 



Diagnosis. — Closely related to Zoroaster alfredi Alcoclc, from 

 which it differs in having longer rays, stouter, conical, carinal spin-js, 

 relatively smaller papular pedicellariae, ungrooved spinelets, less 

 numerous adambulacral pedicellariae, and in lacking, deep in the 

 furrow, the 2 large bunches of pedicellariae characteristic of alfredi. 

 11=282 mm., r=15.5 mm-, R=18 r. Breadth of ray at base, 17 mm. 

 Disk very small, fairly level on top in large specimens, tumid in 

 small ; rays slender and stronglj^ carinate, the carinal plates forming 

 a definite spiniferous ridge; median tube-feet smaller and more 

 crowded than the lateral. 



Desonption. — Primaiy plates of disk fairly conspicuous, but, like 

 the others, covered with slender, rather long hirsute spinelets, inter- 

 spersed among which, on the papular areas, are several large 2- jawed 

 pedicellariae. The primary plates bear a central robust spine, much 

 stouter and a trifle larger than the spinelets. Carinal platos foi-ni- 

 ing a conspicuous ridge, each with 2 lobes on either side which 

 overlie and partly cover the small adradial plates. Between the 

 adradial plates and adambulacrals, at base of ray, 7 series of 

 plates, which are tumid and have 4 obtuse lobes by which they 

 imbricate. The plates increase in tumidity toward the furrow. 

 Plates covered M'ith slender, relatively long, slightly spaced unequal 

 spinelets, which, however, var}^ in length on different specimens, 

 but are much longer and more hirsute than in the carlnatus group. 

 These spinelets increase slightly in length toward the furrow. Each 

 carinal plate has a central robust conical spine or sharp, deciduous 

 tubercle of variable length but very much thicker and usually de- 

 cidedly longer than the spinelets. The other plates (except the 

 small adradials) bear a central, conspicuous, slender, tapering, sharp 

 spine, that of the superomarginal about 1 to 1.5 plates in length 

 while those adjacent to the adambulacrals are 2.5 plates in length. 

 The spines of the lower 3 longitudinal rows are flattened, appressed, 

 and have lengthwise sliallow grooves. The papular areas are fairly 

 large in big specimens, with 1 or 2 papulae. Each area is guarded by 



