208 VERRILL 



there is an additional imperfect interpolated row below the supero- 

 marginals distally. The ventral spines are rather smaller than the 

 dorsals. 



The adambulacral spines mostly form a transverse group of three 

 on the distal plates; but proximally often one and two on alternate 

 plates. The inner or furrow spine is much the smallest, and 

 stands just within the margin; it is tapered, acute, and about half 

 as long as the outer ones. The latter are stouter and acute, but 

 smaller than the marginals. When three are present, the inter- 

 mediate one is intermediate in size. The outer ones are somewhat 

 webbed together at base. 



Interactinal plates and spines are absent. The inferomarginals are 

 united directly to the adambulacrals, the latter being transversely 

 oblong at the surface. Two or three short, irregular rows of inter- 

 marginal ossicles are interpolated between the upper and lower mar- 

 ginals at the bases of the rays. The large spiniferous dorsal ossicles 

 are thick, convex and lobulated. The smaller connective ossicles 

 are rounded and elliptical, thick, or biscuit-shaped ; and many of 

 them have a naked, glistening, round, central area, covered with 

 very uniform minute punctulations. Similar punctate ossicles occur 

 on the lateral and ventral surfaces, between the spines. 



The two apical oral spines, and the pair of epioral spines, are about 

 equal and similar to the adambulacrals, but not so large. The 

 lateral adoral spines are small and strongly divergent. A few 

 solitary papulae stand between the inferomarginal and adambulacral 

 plates. Ambulacral feet and pores are large. Madreporic plate 

 small, prominent, with few rough gyri. 



The type is from Sooke, Vancouver Island (Canadian Geological 

 Survey, 1893), received through Mr. J. F. Whiteaves. 



ECHINASTER TENUISPINUS Verrill. 



Plate cvii, figure 2 (type). 



Echinaster tenuispinus Verrill, Trans. Conn. Acad. Sci., i, pp. 577, S94, 1867. 

 Ives, Proc. Acad. Nat Sci. Philadelphia, 1889, p. 171; List of Echinod., 

 Cabinet of Stearns, p. ii, 1891. Sladen, Voy. Chall., xxx, pp. 554, 812, 

 1889. ?? Clark, Proc. Boston Soc. Nat. Hist., xxix, p. 319, 1901. 



A large five-rayed species with long, tapering rays, swollen at 

 base, but becoming slender toward the tips. Radii, 14 mm. and 

 91 mm. ; ratio, i : 6. This specimen is one of the original types. 



Dorsal spines unusually numerous for this genus, but mostly 

 isolated, rather small, usually i mm. to 2 mm. long, slender, acute ; 



