276 VERRILL 



Professor Fisher records it from a number of localities in Bering 

 Sea, from Bering Strait to Bering Island and Unalaska, and off 

 Kamchatka, in 17 to 85 fathoms. I have also had six-rayed speci- 

 mens from the same region. 



He has found that in Bering Sea it occurs with six to nine rays, 

 but most frequently with six rays. The only nine- rayed specimen 

 was a young one taken from the marsupial pouch of an eight-rayed 

 specimen. One of my eight-rayed specimens also contained a nine- 

 rayed young one. Some of his specimens were much larger than 

 the one described above. The largest six-rayed specimen had the 

 radii 43 mm. and 71 mm. ; ratio, i : 6.5. The largest seven-rayed 

 one had the radii 56 mm. and 82 mm. ; ratio, i : 6. His large 

 specimens had five or six spines in the adambulacral combs, proxi- 

 mally. He did not find genital, interradial slits, showing that they 

 are temporary, for the escape of the young, as suggested above. 



PTERASTER OBSCURUS, var. OCT ASTER Verrill. 



Pteraster octaster VERRILL, Amer. Journ. Sci., xxvin, p. 61, fig. i, 1909. 

 Fisher, 191 ib, pi. cvi, fig. i. 



The Pacific form with eight or nine rays, most commonly eight, 

 seems worthy to retain the name octaster, as a variety. The original 

 description was as follows : 



" Disk large and plump ; margins well defined by points of the 

 actino-marginal spines ; rays eight, short, about as wide as long, sub- 

 acute ; the ambulacral grooves turn up but little at the tips. Radii of 

 the largest example, 20 mm. and 30 mm. 



" Dorsal surface covered with a thick membrane through which 

 the tips of the spinules show but little as pretty uniformly scattered 

 points; in alcohol they form the apex of small, low, conical, fleshy 

 elevations. Central oscule small, in alcohol inconspicuous, its short 

 spines covered by a soft membrane. Ambulacral feet large, in two 

 rows. 



" Adambulacral spines form combs of five or six spines, of which 

 the innermost is much smaller and more slender than the rest, which 

 are rather stout, tapered, subacute, divergent; the outer ones longer; 

 the outermost appressed to the surface. Epioral pair of spines long 

 and rather stout, tapered, translucent distally. The interradial areas 

 are narrow, with rows of long, stout, imbedded actino-marginal 

 spines, the ends of which project a little at the margin of the disk. 



