302 BULLETIN OF THE BUREAU OF FISHERIES. 



Adambulacral plates wide and short and rather closely placed, so that the peculiarly character- 

 istic armature forms a dense mass of spines along margins of furrows; on each plate about 10 stout, 

 subcylindrical, untapered, occasionally slightly compressed, truncate or round-tipped spines, which 

 decrease in size as they recede from the furrow, and are arranged either in 5 longitudinal series of 2 

 or irregularly on outer half of plate; furrow series commonly oblique, and composed of 3 instead of 2 

 spines, or 1 may stand on center of margin and 2 just, behind it; on outer end of plate 5 i>r li robust, 

 smaller spinelets similar to those of actinal intermediate plates, forming a group about the outer spines, 

 into which they grade in size. 



Mouth plates comparatively large, rather prominent actinally, this appearance being accentuated 

 by a depression in the interradial area at their outer end; general surface covered with numerous 

 robust, irregular spinelets, which increase in size and become more compressed toward the free margin 

 of the plate; marginal series beginning at outer (aboral) end, high in the furrow, as rather incon- 

 spicuous flattened lanceolate spinelets, which rapidly increase in size toward inner angle, the innermost 

 being much enlarged, that next to it nearly as much, spatulate or hatchet-shaped and directed toward 

 actinostome, which is almost entirely closed by the mouth plates. The latter, as a whole, have a very 

 dense, bristling appearance, like the adambulacral plates. 



Actinal interradial areas large and paved with superficially oblong plates, arranged in series 

 running from adambulacrals to marginals, there being 10 in the series opposite the first adambulacral; 

 these plates extending far along ray, but not attaining the tip, the number of plates in the transverse 

 rows rapidly then gradually diminishing; each plate bearing on its convex eminence a group of coarse 

 spinelets, which increase rapidly in size toward the center; peripheral spinelets very unequal, rather 

 slender, but the central ones clavate, bluntly pointed, and similar to the centrally situated spinelets 

 of the inferomarginals. 



Madreporic body inconspicuous, situated midway between margin and center of disk, partially 

 bidden by paxilkc; striations tine, but ridges coarse, centrifugal, undulating. 



Locality: Station 4253, Stephens Passage, Alaska, in 188 to lot fms.; rock and broken shells; 

 bottom temperature 40.9°. 



This is a distinct and rather peculiar species, differing widely from either lizardi or cognatus in 

 both the general form, which is flattened, and the spinulation, which is notably coarser and more 

 granuliform on the abactinal surface. The marginal plates are more conspicuous and the furrows 

 between them more marked, while the armature of the adambulacral, mouth, and actinal intermediate 

 plates appears coarser, particularly that of the first 2. The armature of the mouth plates with the 

 spatulate teeth and peculiar furrow series is very characteristic. 



This species is named for Lieut. Franklin Swift, V. S. Navy, commanding the Albatross. 



Family 0D0NTASTER1D/E Verrill, i8uo. 



Genus ODONTASTEE Verrill. 



Odontaster Verrill, Amer. Journ. Science, XX. 1S80. 402 (0. MepidiiS Verrill). 



Odontaster crassus, new species. 



Stellato-pentagonal, with distinct rays. R=21 mm.; r=13 mm. R=1.5 r. Breadth of ray at 

 base, 15 mm. 



Disk large, rays short and blunt, uniformly tapering from the broad base; abactinal surface 

 slightly inflated on radial areas; actinal area subplane; interbrachial angles very wide, shallow, and 

 obtuse; marginal plates massive, conspicuous. 



Abactinal paxilhe large and fairly elevated, arranged very regularly in a medium radial and about 

 parallel rows on either side (at base of radial area); each pedicel surmounted by a radiating group 

 of 15 to 20 slender, tapering spinelets, which are longer than the pedicel or tabuhun; papular pores 

 fairly conspicuous, about each plate, absent from interradial area where the spinelets of paxillse 

 or plates are shorter; basal plates of primary apical system much larger than any of the others; 

 tabuhun low. 



Marginal plates broad and conspicuous; superomarginals forming a raised border to abactinal 

 area; 17 in number to side of body, or 8 to tin' ray; interradial plate larger than the others, subtri- 



