ASTEROIDEA OF NORTH PACIFIC AND .VDJACENT WATKRtj — FlSUIiR. 233 



compressed; on actinul surface opposite tlie outer furrow spine one compressed 

 spine nearly as lon<;, and on the inner part of tlio plate usually another, considerably 

 shorter, connected with the first by a linear series of several spaced, unequal, conical 

 granules, which are continued beyond the outer spine to the end of (ho plale, there 

 forming a group rather than a row. 



Actinal interradial areas large, three series of intermediate plates extending 

 to the fourth inferomarginal, two to the fifth, and one to the ninth; each of the 

 plates adjacent to the adambulacrals bears a large, sessile, bivalved pediccUaria, 

 4 mm. in length, similar to those of dorsal surface, j>laced usually obliquely cross- 

 wise. Numerous other interradial plates also have a pedicellaria, usually some- 

 what smaller. Plates also armed with one or two conical spinules or tubercles 

 standing on the edge, often on cither sitle of the pedicellaria, in line with a perii)heral 

 scries of large and small hemispherical or acorn-shaped granules. Plates without 

 pedicellarijp bear one or two unequal thimble-shaped si)ines surrounded by a 

 peripheral series of small granules, with two or three here and there larger than 

 the others. All the actinal interradial spines are shorter than the marginal. 



Madreporic body small, circular, situated slightly nearer center than midway 

 to margin; striations fine, ridges rather wide. 



Type.— Cat. No. 22338, U.S.N. M. 



Ti/pe-locality. — Albatross station 4239, Clarence Straits, Alaska, 206 to 248 

 fathoms, coarse sand, rocky. (Cruise of 1903.) 



Distribution.— \\.no\yn only from the type-locality. 



Specimen examined. — The unique type. 



Remar'Jcs. — This species diiTers from all the preceding, as well as from phn/gi/irut, 

 in having the abactinal granules, which are small and more or less conical, scattered 

 over the plates and not arrangetl in a definite marginal series; by the preponderance 

 of the large low bivalved pedicellariie over the spines; by the characteristic form of 

 the abactinal skeleton and the soft investing membrane; in having large and 

 numerous marginal pedicellaria-; in the presence of two actinal adambulacral 

 spines instead of one; in having conspicuous stout actinal spinelets. The pedi- 

 cellaria? on heatld are very large and have lower jaws than in any other s])ecies of 

 IHppasteria. The abactinal spines are also slightly different, being thicker and more 

 conical, and the papulae are very conspicuous, being tlistributed all over the abactinal 

 surface. The scattered granules and rather thick soft abactinal membrane make 

 it impossible to distinguish the outlines of the ])lates, even in the dried condition. 

 No such difiiculty is encountered in other species of IHppasteria. 



HIPPASTERIA CALIFORNICA Fisher. 



n. 45, figx. 1-4; pi. 60, fig. h; pi. Ill, fig. 1. 

 Eippasleria call/ornica Fisher, Bull. Bur. Fi.-heries for 1904, vnl. LM, June 10. 1905, p. 310. 

 Diagnosis. — Disk broad; rays broad ami rather short, tapering from a broad 

 base to a bluntly pointed extremity; interbrachial arcs very wide, shallow, and 

 rounded; abactinal surface subject to inflation; disk thinner than in plin/(jiana. 

 Abactinal surface spiny, as in spinoso, but tyi)ically with fewer sjnnes. Marginal 

 plates small, oblong-elliptical, often separated by encroaching abactinal and actinal 

 int<?rmediate plates, typically with one conspicuous spme. Adambulacral plates 



