NORTH PACIFIC OPHIURANS IN NATIONAL MUSEUM CLARK. 167 



2 specimens; Puget Sound, 1 specimen; Monterey, California, 8 to 12 

 fathoms, 4 specimens. Bathy metrical range, 8 to 240 fathoms. 

 Temperature range, 49 to 44. Eighteen specimens. 



As no figures of this species have been published, it has been 

 thought desirable to give the accompanying illustrations. The char- 

 acteristic mouth parts easily distinguish this species from afty-of 

 the others taken by the Fisheries steamer Albatross. In fact, it is 

 the only representative of its genus in the collection. 



AMPHIOPLUS RHADINOBRACHIUS, new species.a 



Disk 6 mm. in diameter; arms about 100 mm. long. Disk covered 

 by a coat of several hundred scales, of nearly uniform size. Radial 

 shields long and very slender, in contact distally but separated within. 

 Upper arm plates much wider than long, strongly convex distally ; at 

 base of arm angular proximally, and slightly in contact, but farther 

 out broadly convex proximally, and separated from each other. 

 Interbrachial spaces below covered with much smaller scales than 



FIG. 73. AMPHIPHOLIS PUGETANA. X 12. a, FROM ABOVE; ft, FROM BELOW; c, SIDE VIEW OF THREE 



ARM JOINTS NEAR DISK. 



those of the disk. Genital slits large. Oral shields oval, longer than 

 broad. Adoral plates large, narrow within where they nearly or quite 

 meet, very much broader at outer ends. Oral papillae four on a side, 

 one thick and rounded at apex of jaw, the second and third nearly as 

 large, but flat and rounded or pointed at tip, the fourth somewhat 

 smaller; the tentacle scale of the first oral pore shows between the 

 first and second papillae and may be mistaken for another papilla. 

 First under arm plate minute, pentagonal, about as long as broad; 

 succeeding plates pentagonal or hexagonal, broader than long, be- 

 coming longer than broad, distinctly in contact, at least on base of 

 arm. Side arm plates small, meeting above except at base of arm, not 

 meeting below; each plate carries three sharp, slender spines, sub- 

 equal, or the middle one longest. Tentacle scales, two. Color (dried 

 from alcohol), light gray or whitish. 



, signifying slender, and /fywz^/wv, signifying arm, in reference to the very 

 slender arms. 



