478 THE FUR SEALS OP THE PRIBILOF ISLANDS. 



151. Careproctus ostentum Gilbert. 

 Recorded from near Unalaska, 



152. Careproctus phasma Gilbert. 

 From Bristol Bay. 



153. Careproctus spectrum Bean. 

 From near TJnga. 



154. Careproctus coUetti Gilbert. 



From waters to the south of Alaska peninsula. 



155. Careproctus ectenes Gilbert. 

 From near Unalaska. 



156. Careproctus gelatinosus (Pallas). 

 Petropaulski; not recognized by recent writers. 



157. Frognurus cypselurus Jordan and Gilbert, new genus and species. (Plate LXXVII.) 



This species is most nearly related to Careproctus melanurus, from which it differs 

 in darker coloration and shorter gill slit. From all known species of Careproctus it 

 differs in the very elongate caudal fin, which is forked at the tip. The feature defines 

 the genus Prognurus. 



Head 4f in length; depth, -li^o; cleft of mouth, 1% in head, seven-fifths distance 

 from symphysis of lower jaw to angle of mouth; total interorbital width, 2| in head; 

 eye large, equaling length of snout, 3f in head; gill opening entirely above base of 

 pectoral, not reaching base of upper ray, its length 3 in head; the opercular lobe 

 broadly rounded. 



Snout blunt, broadly rounded, the mouth horizontal along its lower margin, 

 scarcely overlapped by it. Upper lip wide. Teeth acute, without cusps, in about 27 

 oblique rows in one side of each jaw. Maxilliary reaching the vertical from posterior 

 edge of the pupil. Nostril opening in a wide, low tube. 



Front margin of ventral disk very slightly behind angle of mouth, its diameter 

 three-fifths that of eye, about one-seventh length of head. 



Pectorals broadly rounded, regularly shortened below, not deeply notched, the 

 lower 7 rays thickened and exserted ; the longest free ray about half length of head. 

 Upper portion of fin with 26 rays, the tips only protruding, the longest equaling 

 length of head. Dorsal beginning shortly behind vertical from gill slit, its distance 

 from tip of snout 3^ in length. Dorsal with about 58 rays. Caudal very long and 

 narrow, only its basal third connate with last rays of dorsal and anal. Unlike all 

 other Liparids, the caudal is forked at tip, the terminal notch, involving about one- 

 seventh of fin. 



Translucent dusky, darker around snout^ gill openings, and on the fins, the verti- 

 cal fins largely jet-black. Mouth and gill cavity dusky, not black. 



Type a single specimen, 21 cm. long, dredged at station 3644, off Bogoslof Island, 

 at a depth of 664 fathoms. A second specimen was obtained by t\iQ Albatross in 1889 

 at station 3074, off the coast of Washiugton, in 877 fathoms, but it was too seriously 

 mutilated to admit of description. 



158. Rhinoliparis barbulifer Gilbert. 

 From deep water off Unalaska. 



