118 BULLETIN 7<>, UNITED STATES NATIONAL MUSEUM 



slightly developed, sometimes suppressed. Straight pedicellariae ovate or triangular 

 ovate similar to those of aequalis. (PI. 45, figs, lc, Id, le.) 



Type. — In the British Museum. 



Type locality. — "Vancouver Island." The specimen is so like the prevalent 

 form from the San Juan Islands that I think it probably came from that region. 



Distribution. — Puget Sound and adjacent regions of the Strait of Fuca and 

 Strait of Georgia; shore to 60 fathoms. 



Specimens examined. — One hundred and twenty-six. 



San Juan Islands, Wash. (Friday Harbor and Orcas Island) intertidal; a few 

 from 20 to 25 fathoms. 



Seventy specimens of Classes I and II; 56 specimens of Class III, some of which 

 are young of vancouveri, others either forma hexactis, or facsimiles. 



Remarks. — Some of the specimens of Class III, enumerated above, are L. 

 hexactis forma hexactis for ordinary purposes, and no diagnosis can be given which 

 will separate them effectively from the types of L. hexactis. Yet some of Class III 

 are undoubtedly the young of Class II, probably also of Class I (typical vancouveri). 

 In all probability the type specimens of hexactis have nothing to do with vancouveri, 

 but are variants of regularis. The logic therefore is that some of the specimens of 

 Class III are genetically quite different from L. hexactis, although so similar in 

 appearance. 



LEPTASTERIAS PUSILLA, new species 



Plate 45, Figures 3, Za-Zd; Plate 46, Figures 2, 2o-2d; Plate 54, Figure 5; Plate 55, Figures 1, 2, 7. 



Leptasterias hexactis Verrill, part, Shallow-water Starfishes, 1914, p. 127 (Monterey). 



Diagnosis. — Differing from the slender phase of L. hexactis f. hexactis in its con- 

 stantly small size, in the different dentition of the crossed pedicellariae and different 

 shape of the straight pedicellariae which are constantly narrow-ovate or elliptical in 

 contour. Rays six, slender, subterote, tapering from a narrow base; disk small. 

 R 22 mm., r 5 mm., R =4.4 r (varying to 5 r) ; breadth of ray at base 5 mm. Spinelets 

 small, slender, spaced, the carinal plates with proximally one to three and the dor- 

 solaterals with usually ono spinelet, all without serial order or else in five poorly defined 

 longiserios; superomarginals, two, sometimes three, inferomarginals two; actinals one. 



Description.— Abactinal spinelets (pi. 46, figs. 2, 2a, 26) slender, longer than 

 thick, terete to subclavate, thorny, one to three to a plate on disk; on rays one to 

 three to a carinal plate; ordinarily one, occasionally two to a dorsolateral. Spinelets 

 0.3 to 0.4 mm. long, spaced by about their own length. They are arranged in about 

 five not very regular longiseries of which the median or carinal, composed of groups 

 of two or three spinelets, is not conspicuous as in aequalis. The dorsolateral plates 

 occasionally carry two spinelets. In some specimens the spinelets are not arranged 

 in definite longiseries. Size of papular areas variable. In one variety they are longer 

 than plates of ray and the skeleton appears open, while in the other the areas are 

 subequal to the plates or smaller. Papulae one to an area. 



Superomarginal plates not conspicuous, four lobed with two slender spinelets 

 similar to but a trifle longer than the dorsals, one on the dorsal, one on the ventral, 

 and occasionally a third on the adoral lobe. 



