246 VERRILL 



regularly in alternating obliquely transverse rows, or in quincunx, 

 and are a little larger and bear twelve to eighteen or more divergent 

 webbed spinules around the edge and four to six or more on the 

 central part. On the distal part of the rays the ossicles become 

 smaller, more closely crowded, and imbricated, with their regularly 

 stellate spinules in contact. Many of these have only nine to twelve 

 spinules around the edge and one to three in the middle. 



The adambulacral plates mostly bear two unequal furrow-spines, 

 but some proximal ones bear three, the central much the larger ; dis- 

 tally they mostly have but one. 



NORTH PACIFIC SPECIMENS. 



A ten-rayed specimen taken off Kadiak, Alaska, in 5 fathoms, by 

 the Harriman Expedition, agrees well with New England specimens 

 of the same size. Its color in life was " orange with purple bars " 

 (Coe). 



Radii, 25 mm. and 65 mm. ; ratios, about i : 2.6. The rays are 

 convex above and taper to rather slender tips. Dorsal surface 

 closely and evenly covered with small, stellate pseudopaxillae, which 

 do not form any distinct radial rows, but often are in contact by 

 their edges. When expanded they are unequal, mostly circular and 

 regularly stellate, each having from nine to fifteen or more minute, 

 divergent spinules, webbed together around the edge, and two to 

 four in the middle. They are borne on very small, convex, mostly 

 four-lobed ossicles, between which are numerous isolated papular 

 pores, each of the larger pseudopaxills having three to five around 

 it. On the sides of the rays the pseudopaxillae are in pretty regular 

 quincunx order. 



Central (nephridial) pore distinct. Madreporic plate large, with 

 several pseudopaxillae on its surface. 



Superomarginal pseudopaxillae small, but more than twice as 

 large as the dorsals, with numerous larger, closely clustered spinules. 

 They are round or ovate, close to the upper side of the inferomar- 

 ginals, with which they alternate. 



The inferomarginals are much larger and more prominent, trans- 

 versely oblong, elliptical, and convex or rounded at the summit, and 

 covered with minute, rough, acute spinules, like those of the back, 

 but rather larger. Of these about twenty-five to forty surround the 

 margin, while about fifteen to twenty form a central row. 



A row of peractinal plates extends to about the middle of the free 

 part of the rays, decreasing rapidly distally. The proximal ones are 



