442 THE FUR SEALS OF THE PRIBILOF ISLANDS. 



Family PLAGYODONTID^E. 



44. Plagyodus aesculapius (Bean). 



A specimen 4J feet long came ashore at Summer Harbor, Unalaska, August 29, 

 and was taken alive by James G. Blaine, United States Marshal at Unalaska, who 

 has presented it to the United States National Museum. Another specimen ran 

 ashore alive at Unalaska the preceding year. The species is said to be common in 

 that locality. The following is a description of the specimen when fresh: 



Head, 6i; depth, 13; D., 40; A., 16: V. I., 8; P., 13 or 14. Length of longest 

 dorsal ray, 5| in body; pectoral, 1--^ in head; ventral, 3^ in head; longest ray of 

 anal, 2 J in head; maxillary, IJ; snout, 2J; eye, 6J. 



Body not much compressed, the flesh somewhat pellucid and gelatinous, covered 

 with thin, smooth, mackerel-like skin. Lateral line beginning anteriorly above level 

 of eye, becoming straight at about two-thirds distance from its origin to ventral, 

 where it gradually rises to a high fleshy keel, black in color, and conspicuous nearly 

 all the way from the ventrals to caudal. Maxillary with many small teeth in an 

 irregular series or narrow band; lower jaw laterally with 11 stout, saw-like teeth 

 turned backward, then with three much longer but similar teeth directed backward, 

 their length about half diameter of eye; a slender canine on each side at tip of lower 

 jaw; then about 8 short, slender, sharp teeth between these and the enlarged lateral 

 teeth already described. Front of vomer with three immense fixed canines as long 

 as eye, two close together in front, one behind them, all sharp, flat, and knife-shaped. 

 Palatines each with a stout compressed canine like those in side of lower jaw; then 

 five broad, close set, saw-like teeth behind it. Opercles with strong striae which 

 radiate from the upper anterior corner; these not parallel with the strong subhori- 

 zontal strise of the subopercle. Lower jaw with striae which radiate from behind. 



Eye very large, two sharp, low ridges above it; interorbital space broad and 

 smooth; gill rakers small, few, and sharp; pseudobranchiae present, a membrane 

 below them joining the first gill arch. 



Pectorals long, the first ray broader than the following, strongly serrate on outer 

 edge; first ventral ray with a few distant serrations, mostly confined to basal portion. 

 Ventral fins small, few rayed, inserted at a distance behind the head nearly equal to 

 twice its length. Dorsal much lower than in a specimen from San Luis Obispo County, 

 Oal.,' the first ray serrulate inserted just behind gill opening; adipose fin high and 

 long, narrower at the base than above, inserted but little behind middle of anal. 

 Caudal unequal, slightly forked, the upper lobe the longer; caudal peduncle slender, 

 as thick as deep. 



Color dusky gray, not silvery anywhere, but with metallic reflections. Pins and 

 lateral keel black; lower side of head whiter; some green shades in eye, and dull 

 blue luster on dorsal fin. 



Family STERNOPTYCHIDy^. 



45. Sternoptyx diaphana Lowe. 



Pour fine specimens found by the schooner Allen floating at the surface off Kurile 

 Islands, said to have been with many others killed by the earthquakes. We can not 

 see that these differ from Atlantic specimens. 



1 Notes on a specimen of Alepisaurus aaculapius Beau, from the coast of San Luis Obispo County, 

 Cal. Flora Hartley (Mrs. C. W. Greene), Proc. Cal. Acad. Sci., V, 1895, 49. 



