300 BULLETIN 76, UNITED STATES NATIONAL MUSEUM. 



mediate plates die out these two series of papula) merge into a single series (one or 

 two papulic to an area) between inferomarginals and adambulacrals. 



Adambulacral armature consisting of (1) a saber-shaped spinelet situated deep 

 in furrow, unusually prominent, and capped by a short membraneous tip; when 

 bent outward this spinelet reaches about three-fourths across furrow. (2) On acti- 

 nal surface a rather long slender tapering bluntly pointed spine stands on margin 

 and behind it two similar spines in an oblique transverse series, the inner of these 

 two forming also an oblique series with the marginal spine. Behind these are three 

 or four slightly shorter and sharper spinelets, in a coordinate group, the outermost 

 spinelets the shortest of all. The spinelets stand in a zig-zag transverse series. 

 Occasionally the spinelets form a nearly straight series across the plate. Adam- 

 bulacral spines larger than any others. 



Madreporic body large, situated near edge of disk and covered with numerous 

 spinelets similar to those of pseudopaxillse. 



Color in life, milky white ; in alcohol, the same, or yellowish. 



Variations. — A smaller specimen from station 4228, vicinity of Naha Bay, 

 southeast Alaska, and consequentlj^ from near the type-locahty, maintains the 

 general facies of the type, but has only one or two papulas to each area, few inter- 

 marginal pseudop axillae, ami spmelets which are relatively slightly longer than in 

 type (11 = 25 mm.). 



Type.— C&t. No. 277S3, U.S.N.M. 



Type-locality. — Station 4199, Queen Charlotte Soimd, off Fort Rupert, Van- 

 couver Island, British Columbia, 107 to 68 fathoms, soft green mud, volcanic sand. 



Distribution. — From the vicinity of Vancouver Island to southern Alaska. 



Spemnens examined. — In addition to the tyj^e, one specimen from station 4228, 

 vicinity of Naha Bay, Belim Canal, southeast Alaska, 41 to 1.34 fathoms, gravel, 

 sponges. 



Remarlcs. — Tliis species is notable for the prominent fasciculated spinulation 

 and the prominence of the adambulacral spinelets. The spinelets are much longer 

 and shaiper than in sanguinolenta, the groups much more spaced on account of the 

 open character of the skeleton, and the adambulacral spinelets much longer. 



HENRICIA LONGISPINA ALEUTICA, new subspecies. 



PI. 77, fig. 2. 



Diagnosis. — Similar in the character of its armature to Henricia longispina, 

 with wliich it agrees in ha\4ng the spinelets in spaced fascicules, but from which it 

 differs in having a much more open abactinal skeleton with larger papular areas, 

 in having larger intermarginal papular areas, and extensive actinal intermediate 

 areas with numerous plates and papulae. 



Description. — 11 = 98 mm.; r=lS mm.; R = 5.4 r. Breadth of ray at base, 20 

 mm. The whole skeleton is weaker and more open than in longispina and more as 

 in astlienactis, but the sj)inelets instead of being distributed singly along the skeletal 

 pieces (as in asthenactis) arc in fascicular tufts and much longer than in that s]>ecies. 

 Meshes of abactinal antl lateral surface large, three-, four-, or five-sided, without 

 regularity, and ordinarily about four times the diameter of the skeletal pieces, wliile 

 in longispina they are not more than twice the diameter. The papular areas con- 



