39 6 
SPINY-FINNED GROUP. 
the genus Rhynchobdella, characterised by the striation of the lower surface of the 
nasal appendage, and the lack of a spine in front of the eye, is confined to India 
and Burma, where it is represented by R. aculeata, which grows to a length of 
about 15 inches, and is found in the deltas of all the larger rivers, generally 
preferring muddy pools. The figured species is, however, of larger size, reaching 
a couple of feet in length. The flesh of all the spiny eels is stated to be of 
excellent quality for the table. 
The fish represented in the lower portion of the annexed illus- 
Oil-Fish. 1 1 
tration, known as the Baikal oil-fish (Comephorus baikalensis), is 
the only representative of a genus in regard to the systematic position of 
which there is considerable doubt; Dr. Gunther regarding it as indicating a 
distinct family which he at one time placed in the neighbourhood of the oblique- 
indian spiny eel (J nat. size). Baikal oil-fish (J nat. size). 
spined blenny, and afterwards near the flying gurnards. In this fish the body 
is elongate and naked, the head large with a produced muzzle, medium-sized 
lateral eyes, and small teeth. There are two dorsal fins, of which the first is 
much shorter than the second, which is similar to the anal; the pelvic fins are 
wanting, and there is no papilla near the vent. The gill-opening is wide ; there 
are four gills, and no air-bladder. The skeleton is very soft; and the elements 
of the gill-cover are not distinctly differentiated. In colour this strange fish is 
uniformly greenish, and its pectoral fins are remarkable for their large size. 
While the oil-fish presents some resemblance to the dragonets, it differs by the 
compressed body, the large, broad-snouted head, the elongation of many of 
the rays of the second dorsal fin, the large pectorals, the absence of pelvic fins, 
and the forked tail. So far as present information goes, the oil-fish is confined 
to Lake Baikal, where in winter it retires to the greatest depths, but approaches 
