ASTEROIDEA UF NORTH PACIFIC AND ADJACENT WATERS — FISHER. 355 



lateral membrane. Aperture papilla lonjjer than wide, witii slifjlitly convex aboral 

 bonier; the aperture is at tlie base of tlie outermost adambulacrai spine, and is 

 less than one-third its len{;th, sliorter even than the small papilla. 



Mouth plates witli six slender independent inar<rinal spines (no web), the inner 

 the longest, and longer than the intemidial diameter of plates, the outer very short, 

 the others evenly and rapidly gra<luated between. The single suboral spine is 

 vers' slender and a little longer than inner marginal spine. 



Actinolateral membrane very broad, the conspicuous lateral fringe extending 

 1 to 3 mm. beyond the border of ray. The spines are longest at about the middle 

 of ray (seventh to ninth spinel; thence they decrease rather evenly to the tip. the 

 fringe always defining ambitus. 



Type.— C&t. No. 27792, U.S.N.M. 



Type-locality. — Albatross station 292.5 (probably), off San Diego, California, 

 339 fathoms, mud. The bottle in which this specimen was received was broken 

 by the earth(|uake of 1900; the specimen was found beside the above label and 

 the remnants i>f the bottle. 



Distribution. — OlT soutJiern and central California. 2S7 to 1,062 fathoms. 



Specimens examined. -Three; besides the type, one from station 4.339, off San 

 Diego, California. 287 to 369 fathoms, green mud; one from station 4.537, olT Mon- 

 terey Bay, 1,062 fathoms, hard sand. 



Remarks. — This species is related to Pt. muitispinu-s Clark, Pt. reticulatas 

 Fisher, and Pt. iKtiltijiorus Clark, tlie first from Washington, the seconil from the 

 Hawaiian Islands, and the third from Sagami Bay, Japan. From muUispintis the 

 present form differs in having five free slender mouth spines (not three united by 

 membrane), in having a slender suboral spine, much more numerous spiracula, 

 fewer paxillar spines (not eight to ten or more), anil apparently differently formed 

 aperture papilla? (in multispinu-s "nearly free on both siiles"). From reticulatus, 

 coscinopephui difTei-s in being more pentagonal in form, with a verv* much wider 

 actinolateral membrane, and in having slenderer suboral spines (these heavy and 

 club-shaped in reticulatu-s), no supradorsal reticulations, fewer paxillar spines, 

 which consequently form a less closely papillated dorsal surface, and in having 

 man}' more spiracula nf a smaller size. The adambulacral armature dilTers chiefly 

 in size, the fans being larger (and spines longer) in cosciiiopfplu.s. From muUiporus 

 this species differs in having a much wider actinolateral meml)rane (it is narrow in 

 inuUiporus'*. higher paxilla- witli fewer spines, and in having the mouth spines free, 

 not the whole twelve (six of ea<li plate) unitecl by a continuous membrane. 



PTERASTER TEMNOCHITON FUJier. 



ri. 10:i, ligs. 2, 3; pi. 1 !•'■), fig. 3; pi. Ufi, lip<. 3, 3a. 



PUraater Umnochiton F18HKR, .\nn. and Mag. ?*Bt. ni»t.. Her. 8, vol. 5, Feb., 1910, p. 169. 



Diagnosis. ^li&va five. R=21 mm.; r= 16 mm.; R= 1.3 + r. Breadth of ray 

 at base, without lateral fringe, 9 to 11 mm.; with lateral fringe, 12 to 12..5 mm. 

 General form stellato-penlag<mal ; interbrachial arcs shallow; lateral fringe defining 

 ambitus; psemlopaxilhe low with five to S4"ven s])ines: ni> nHiculation; groups of 

 spines independent and spaced; .s<attereil, branched, irregular rods in membrane; 



