92 Proceedings of the Biological Society of Washington. 



Acanthaster brevispinus, new species. 



Diagnosis. — Resembling A. mauritiensis de Lorio, but differing in hav- 

 ing the abactinal spines of disk reduced to mere spinelets, in having 

 smooth or nearly smooth disk spines on both surfaces and in having only 

 2 or 3 furrow spinelets, shorter than the length of their plate, instead of 

 decidedly longer. Rays 14 to 16; madreporic bodies, 3 to 5; R=90 mm., 

 r=51 mm., R=1.76 r. 



Type.— -Oat. No. 37,027, U. S. N. M. 



Type locality. — "Albatross" station 5149, off Sirun Island, Sulu Archi- 

 pelago, vicinity of Siasi, 10 fathoms, coral, shells. 



Distolasterias hypacantha, new species. 



Diagnosis. — Rays 5. R=129 mm., r=8 mm., R=16r; breadth of ray 

 at widest part near base, 14 or 15 mm. Resembling D. mazophora (Al- 

 cock) and D. euplecta Fisher, from both of which it differs in having, on 

 the proximal half of ray, a series of small spines between the adambulacral 

 spines and the inferomarginal spines (of which there are 2). On abactinal 

 surface, between the two superomarginal series, are 3 series of spines 

 proximally, and only 1, the carinal, distally; only 1 kind of major pedi- 

 cellariae present, slender and lanceolate in form ; rays pentagonal in sec- 

 tion, the width of the lateral face proximally being about two-thirds that 

 of either dorsal face (between superomarginal and carinal row of spines) 

 while distally all four are nearly equal ; disk very small, sunken below 

 the dorsal surface of rays; rays constricted at base. D. dubia (H. L. 

 Clark) has shorter, relatively stouter rays, stouter abactinal skeleton, 

 larger major pedicellariae, broader and more flattened outer inferomar- 

 ginal spines, deeply furrowed on the actinal side. 



Type.— Cat. No. 37,032, U. S. N. M. 



Type locality. — "Albatross" station 5417, between Cebu and Bohol, 

 165 fathoms, gray mud and sand, bottom temperature 54.4° Fahr. 



Tarsaster distichopus, new species. 



Diagnosis. — Rays 5. R=48 mm., r=5 mm., R=9.6 r; breadth of ray 

 at base, 6.5 mm. Disk very small, convex; rays long, slender, bluntly 

 pointed; abactinal surface prominently arched, with very slight mid- 

 radial carinal ridge ; actinal surface nearly plane, the sides of ray as de- 

 fined by the 2 series of marginals, nearly perpendicular, but sloping 

 inward toward the furrow slightly. Differing from T. stoichodes Sladen 

 in having 1 adambulacral spine, 1 spine on the midradial plates, promi- 

 nent unguiculate forficiform pedicellariae in the furrow, and biserial 

 tube-feet. 



Type— Cat. No. 37,031, U. S. N. M. 



Type locality.— "Albatross" station 5664, Macassar Strait (4° 43' 22" 

 S., 118° 53' 18" E.), 400 fathoms, hard bottom, bottom temperature 

 43.3° Fahr. 



