ASTEROIDEA OF NORTH PACIFIC AND ADJACENT WATERS — FISUEK. 215 



Variations. — The specimens here considered differ in a few minor details from 

 the typical examples dredged by the Challenger from near the At hint ic entrance 

 to the Straits of Magellan. It is possible that these represent a new and very closclv 

 allied species, but in view of the individual variations exhibited, aad the absence of 

 typical examples for comparison, I would feel considerable liesitation in instituting 

 a new species. Tlie specimen from the Gulf of California points to a continuous 

 distribution along the west coast of the Americas, but there is too little data for 

 any generalization. 



The Alaskan examples liave fewer and convex granules on the abactiual 

 tabula (not truncate anil crowded) and the edges of the tabula are not so straiglit 

 cut but are a trifle scalloped owing to the slightly convex outer edges of the periph- 

 eral granules. The actinal intermediate plates have more distinctly spaced and 

 round-topped granules, appearing hemispherical in some cases. In Sladen's figure 

 the granules appear to be fairly close together and truncate. In the Alaskan 

 specimens the first series of actinal adambulacral granules are sliglitly longer and 

 more spiniform, but as there is some variation even among the few specimens avail- 

 able it is probable that South American specimens are also variable. Tlie Alaskan 

 examples have with one exception more tumid marginal plates; but the size and 

 tumidity of the bare area is quite variable. 



Taking into consideration the eight specimens, tlie contour varies as Sladen's 

 figures of C. i^atagonicus and C. japonicus (PI. 46), all the Alaskan specimens being 

 like C. japonicus with the exception of two young, wliicli are more arcuate. Tlie 

 Gulf of California specimen is also arcuate but not quite so much so as Sladen's 

 figure of patagonicus. Tlie superomarginals are wider tlian long, that is, are trans- 

 versely oblong, but two specimens have the plates narrower than usual. The size 

 of the bare space varies from a third to over a half of the exposed surface of the 

 plate. Usually but a single row of regular granules borders this space on the inner 

 and one-half the lateral margins. One large specimen, however, has the areas 

 nearh- as small as figured b}- Sladen. A small pedicellaria with two tapering or 

 spatulate jaws stands on the edge of the bare space of a few plates. Tlie bare 

 space is smaller on the inferomarginals and the pedicellariae when present have 

 shorter jaws and are sunken in shallow pits. 



The abactinal surface has very regular low tabula, slightly space<l and hexago- 

 nal on the radial papular areas, less regular and tending to roundish on center of 

 disk, square, rhomboid, or even elongate interradially. The primary basal plates 

 are clearly discernible and are larger than any of the othere except the central plate, 

 which with three or four slightly smaller companions surrounds the anus. The 

 radial tabula bear a peripheral series of twelve to fifteen and about four to twelve 

 central rountl-topped low granules, the former slightly the largest. Tlie central 

 granules are polygonal or roundish and do not touch each other. Tlie peripheral 

 have the outer margin longest. In typical patagonicus as figured by Sladen the 

 central granules are more numerous, crowded and flat-topped, and the edges of the 

 periplieral are more squarely cut, as if "dressed" with a knife. In Alaskan exam- 

 ples the outer edges of the granules are usually fairly straight, but the granules are 

 not crowded, so that the edge of the tabulum is not such a straight line. In one speci- 

 men (station 3257) there is a row of scattered pedicellariw parallel to and about 



