y 



Vol. 30, pp. 89-94 May 23, 1917 



PROCEEDINGS 



OF THE 



BIOLOGICAL SOCIETY OF WASHINGTON 



\ 



NEW STARFISHES FROM THE PHILIPPINES AND 



CELEBES.* 



BY WALTER K. FISHER. 



The following new sea stars were collected during the Philip- 

 pine cruise of the U. S. Fisheries steamer Albatross, 1907-1910. 

 Dipsacaster imperialis, new species. 



Diagnosis. — Differing from D. nesiotes Fisher in having broader rays, 

 more delicate, longer, and sharper paxillar spinelets, in averaging 1 or 2 

 additional true furrow spines to each adambulacral plate, and in having 

 an odd interradial series of actinal intermediate plates, which reach only 

 a little more than half the distance between the outer end of combined 

 mouth plates and inferomarginals. Differing from D. sladeni Alcock in 

 respect to the inferomarginal spines which are smaller and do not form 

 a definite transverse series, especially on the proximal plates ; in having 

 the distal marginals alternating, instead of opposite, and in having more 

 numerous actinal intermediate plates on the ray, the second longitudinal 

 series extending to the twenty-third or twenty-fourth inferomarginal, and 

 the third extending to the sixteenth. R=160 mm., r=55 mm., R=3r— ; 

 breadth of ray at base, 62 mmi. Rays broad at base, tapering from 

 arcuate interbrachia, at first rapidly, then more gradually. Paxillae with 

 numerous (80-90) slender, sharp, glassy spinelets in a brush-like group. 

 Three oblique transverse series correspond to each superomarginal 

 plate; the latter 38 to 40 in number, block-like, only a trifle wider than 

 long in middle of ray. Inferomarginals with a tuft of enlarged spinelets 

 on ambitus. Furrow spines 8 or 9, rectangular in section, compressed, 

 bluntly pointed, lanceolate in contour, the edge to furrow. Subambulac- 

 ral spines 25 to 30, of which 4 to 6 form a regular series back of the 

 furrow series. Madreporic body large, 12 mm. in diameter, situated 14 

 mm. from inner margin of superomarginal plates, and concealed by about 

 25 paxillae. 



Type.— Cat. No. 37,037, U. S. N. M. 



Type locality.— "Albatross" station 5115, Verde Island Passage, north 

 coast of Mindoro, 340 fathoms. 



* Published with permission of the Commissioner of Fisheries. 



22— Proc. Biol. Soc. Wash., Vol. 30, 1917. (89) 



