402 REPORT OF COMMISSIONER OF FISH AND FISHERIES. 
longed rays or conspicuous color marking. The dorsal fin has a median black bloteh ) 
and the caudal is slightly dusky on posterior half. 
23. Salvelinus malma (Walbaum). Dolly Varden Trout. 
The Dolly Varden trout was found to be very abundant in the neighborhood of 
Unalaska, sea-run individuals congregating in great numbers at the mouths and inthe 
lower course of streams when the salmon were running in to spawn. A small stream 
entering Captain’s Harbor, Unalaska Island, has a series of impassable cascades_ 
aggregating several hundred feet in height. Above these falls the trout are very 
abundant, but are dwarfed in size and remarkably brilliant in coloration. They 
seem to reach no larger size than 8 inches. The largest individual seen during 
the season was captured in Makushin Bay, Unalaska Island, August 17. It was 24 
inches long, with a depth of 6 inches, and weighed 6 pounds. The species was also 
seined in salt water in Chernoffski Harbor, Unalaska Island. 
The black-spotted trout (Salmo mykiss), reported by Dr. Bean, from Unalaska, was 
not seen by us. Its occurrence there must be exceptional. 
Family MICROSTOMID4. 
24. Bathylagus borealis sp. nov. 
A single specimen, 132 mm. long to base of caudal, from station 3327 (north of 
Unalaska Island, depth 322 fathoms), is taken for the type. A second specimen from 
the same region, station 3325, depth 284 fathoms. 
Head 4,1; to base of caudal, depth 52, eye 24 in head, snout 22 in eye. Interor)bital 
width grooved, the groove widening posteriorly, opening onto the flat occipital 
region, which is not swollen. Width of cartilaginous portion of interorbital space 
one-third orbit; including the thin membranous plates which overarch the orbits, 
the interorbital width is three-fourths orbit. The anterior profile of snout declines 
gently, bringing the mesial portion of premaxillaries on a level with lower margin 
of pupil. Distance from tip of snout to end of maxillary slightly exceeding 
length of snout, 24 in orbit. Opercle with two strong ridges diverging downwards 
and backwards from hehind the eye. 
Front of dorsal midway between front of snout and adipose fin. Base of dorsal 
contained 34 times in length of head. Ventrals inserted under posterior portion of 
dorsal. Free portion of adipose fin very long and narrow, rising above the base of 
the second and third anal rays before the last, its tip reaching rudimentary caudal 
rays when depressed. Anal fin rather long, the base 1? in head, the vent immediately 
before it. Length of tail much exceeding head, 3? in total length without caudal. 
Dorsal 8; anal 19; ventral 8; pectoral 8. Scales in about 40 rows, judging from the 
scars. Head scaleless. 
Uniform blackish-brown on sides, the head and ventral region blue-black. 
Differing from B. pacificus in its much greater depth, longer tail, longer anal fin, 
and flat occiput. 
Family CHAULIODONTIDA. The Viper Fishes. 
25. Chauliodus macouni Bean. 
Two specimens were secured, one at station 3340, south of the Alaskan Peninsula, 
at a depth of 695 fathoms; another at station 3347, off the northern coast of Oregon, 
at a depth of 345 fathoms. It is not evident in what respects the Pacific form differs 
from C. sloani of the Atlantic, but as no specimens of the latter are at hand for 
comparison we follow Dr. Bean in holding them distinct. 
26. Cyclothone microdon (Giinther). 
Taken in Bering Sea, southwest of the Pribilof islands, at stations 3307 and 3308; 
depths 1,033 and 1,625 fathoms. 
