ASTEROIDEA OF NORTH PACIFIC AND ADJACENT WATERS FISHER. 



379 



row of five flattpiiod spinolots, llio inner tho shortest, tlip otitor llio lon<;est, tlic rest 

 <iriuluat<'(l hctwoon. Somotinios tlio next to outer is lonfjest. 'I'lii' aperture papilln; 

 are hu'ijer as in ixrisxnnotus. The specimen has K. 72 mm. and tlie characters of 

 paxiihe, ahactinal jjhites, suprachu-sai membrane, spiracula, act inoiateral spines and 

 membrane are al)solutely typical of ptrissonolus. As this aberrant specimen wait 

 taken with (juodrixpiitosus, it is possible that it is a hybrid between that species and 

 /)f7'iss()no<HA", althongh no typical examples of the latter were taken at vt.itii.n 's.'.'t 



A six-rayed specimen is present in the lot from station 3074. 



Type.— Cat. Xo. •.'TTOti, U.S.N.M. 



Tiipc-localitij. — Albntros.'^ station 2019, olV Cortes IJank, west of San Dieijo, 

 (.'alifomia, 984 fathoms, (jray mud. 



Distribution. — From San Diego, California, to Bering Sea, L'2.i to 1 ,771 fathoms. 



Specimens ejcamined. — Seventy-eight, from the following localities: 



Speciviriis of Ilymt-nantiT jMTisKonotus examined. 



Naltire ol bottom. 



on Cortes Bank, west of San DIcgo, 



Caliromla. 

 OS Sea Lion Rock, Washington 



.do. 



3074 

 3075 



3227 Bering Sea (north of Unalaska). 



3307 ' Bering Sea (northwest of Vmnnk 



I Island). 

 3342 o j Off Queen Charlotte IsUnds. British 



' Culumbia. 



3346 1 on Tillamook Bay, Oregon 



SCOlo I Bering Sea. between Prlbllot Islands 



I aitd Unalaska. 

 3fi03 1 Bering Sea (east of Pribllol Islands)... 



I No locality » , 



gray mud . . 

 green mud. 



green ooze., 

 gray ooze... 



786 green mud . 

 1.044 i green mud. 



1,771 blueooie.. 



U.S. Nat. Mus. 



Do. 

 Da 

 Da 



Do. 

 Do. 



I Bottles broken during earthquake 1900, but label probably correct. 



' Bottle broken during earthquake liMt. 



Remarks. — This species falls under section B, sub-b. b, of Sladen's ChaUenger 

 Synopsis, although it does not quite agree because there may be three adambuia- 

 cral spinelets on some plates, and only three paxillar spinelets. Of the four species 

 mentioned, ptrhsonotus most resembles x-ic(iriu.<<, from off Chile, \.'Mrt fathoms. 

 It diffei-s from glaucus in lacking the conspicuously defined radial areas rai.^ed in 

 relief above the rest of the abactinal surface. Krom vicariu.i, pirissoiidtii.i differs in 

 having the meilian radial paxilhr very much smaller than the lateral, in having three 

 or four, not four, five, or six jjaxillar spinelets, in having a more pentagonal contour, 

 with tlie actinolateral spines increasing in tliickness at about the middle of ray.anti 

 in having sometimes three, as well as tw(», adambulacral spinelets. From pfllucidtis, 

 pfrissortolu.i differs in respect to the size of the |)axilhe, and in having fewer paxilla 

 spinelets, more numerous muscles in the stipradorsal membrane, a thicker less 

 transparent membrane, and more numerous and large spiracula. //. pillucuiuji 

 has four conspicuous rows of paxiihe along each ray. //. inj'rrnoh.'i has a stollat<> 

 contour, eight to ten paxillar spinelets, and none of the more salient characteristics 

 of //. prrissonolus. Among the species with three adambulacral spineleis. figured 

 by Sladen, perissonotus resembles nu)st //. mmbraiuicru-s Wyville Thomson, fmm 



