ASTEROIDEA OF NOBTH PACIFIC AND ADJACENT WATERS — I-ISUER. 293 



Remarks.— T\^is form may be tlistinguislicd from aspira by the sumllor pafnilar 

 areas, the raised f^'oups of spinelets (iii aspcra tlie spinelcts are scattereil alon<^ tlie 

 ridges surrounding papular areas and never form pseudoj)axilla'), by tlic coarser 

 spinelets, larger nundinal plates, and more numerous adambulacnd spinelets, 

 the outer of which are never immersed in membrane; there are two rows of adam- 

 bulacral spinelets instead of one. From Itduscula the present variety is separated 

 by the more open abactinal skeleton, smaller and more spaced pseudopaxillae, 

 thinner marginal i)ldtes, and the incomplete actinal intermediate series. A 

 comparison of photographs will make the distinctions more apparent. 



HENRICIA ASPERA FUtaer. 

 n. 75, figs. 1-5. 

 Henricia aspera Fi.sher, Proc. Wash. Acad. Sci., vol. 8, Aug. 14, 1906, p. 127. 



Dia^nosi^. — General form slender (but not invariably so); rays long, disk 

 small; skeleton forming a wide, open meshwork with large jiapular areas, which 

 are rather deeply sunken between the narrow ridges; abactinally the larger meshes 

 have seven to ten papula-; spinelets very small, sharp, generally immersed in mem- 

 branous covering of body and arrangeii along the sunmiit of the trabecular ridges 

 in one or two irregular scries; a regular series of superomarginals, inferomarginals, 

 and actinal intermediate plates (the latter extemlhig half or three-fourths length 

 of ray); a series of intermarginals extending a varying distance in some specimens; 

 also a second series of actinal uitermediatc jjlatcs; adambulacral plates with six to 

 eight coai-se spinelets in a single zigzag or a double series, the two nearest furrow 

 margin more or less thickened and considerably larger than the rest; deep in furrow, 

 one or two spinelets. 



Description. — Rays five. Tj^pe, R = 100 mm.; r = 15 mm.; R=6.6 r; breadth 

 of ray at base 14 mm. A slenderer rayed form: R = 80 mm.; r = ll nun.; R = 7.2r. 

 A large thick-rayed specimen with the arms swollen at base R = 107 nmi.; r = 20 

 mm.; R = o.3 r; breadth of ray at base, i23 mm. The abactinal skeleton forms an 

 open jacshwork, jnuch as in //. Jtijadesi (Perrier), the individual plates being indis- 

 tinguishable and sj)inclets very short granuliform, not arrange*! in evident pseutio- 

 ])axill!e as in leviuscula. Meshes are roundish quadrate, or irregularly polygonal, 

 more open in some examples than in others, containing sometimes one or two sjnall 

 secondary ossicles with a few granuliform spinelets. Meshes usually considerably 

 wider than inclosing trabcculse, and with five to twelve papulte on proximal two- 

 thirds of ray, five to seven distally (but fewer in small specijuens). Spinelets not 

 crowded but spaced, short, sharp, nuich shorter and fewer than in lei-iuscula, ohen 

 reduced to nuTC granulifurjii sharp elevations on the ]date and more or less obscured 

 bj' a tight thin skin; arranged along ridges irregidarly, but in not over three rows, 

 often in onlj- one irregular scries. These rows are interrupted, diviiiing the spinelets 

 and granules into groups j^robabh* corresponding to underlying plates, although 

 no divisions are evident. There are conunonly five to fifteen spinelets in one of these 

 groups, but in some specimens they are so obscured by the superficial juembranes 

 that only the very tips of the spinelets are visible. They are invisible to the naked 

 ej^e, ami are seen only with a strong glass. Division into groups more evident on 

 sides of ray. 



