308 Mr. A. Alcock on the Batkybial Fishes 
The snout is a little less than half the length of the head, 
or 6 1 in the total without the caudal. 
The eyes are very large and extremely prominent ; the 
major diameter of the globus oculus is slightly over \ the 
head-length, but owing to the encroachment up to the mar- 
gin of the cornea of the broad posterior orbital fold, the 
diameter of the exposed u eye ” is only a little more than i 
of the same standard ; the true (bony) interorbital space is 
less than half the diameter of the eye in width. 
Nostrils situated high up, above the anterior orbital angle. 
Mouth at the extreme end of the tubular snout, small, the 
jaws apparently with limited motion. The upper jaw, which 
projects slightly beyond the lower, is formed in its anterior 
half by the premaxilla, in its posterior half by the maxilla. 
Minute, acute, recurved teeth in a single row in the pre- 
maxillse and mandible ; no teeth in the maxillae. 
Gill-openings very wide below, contracted above, and not 
surpassing the level of the pectorals. Gill-covers apparently 
complete ; their constituent bones, including the branchio- 
stegal rays, though well calcified, are extremely thin and 
fragile, and are completely concealed within a continuous 
uniform investment of confluent external skin and internal 
mucous membrane. Four gills, with narrow* laminas and 
coarse lamellae ; the fourth gill-cleft wide ; gill-rakers well 
developed on all the arches, moderately long on the first, 
short on the fourth and fifth. Pseudobranchiae rudimentary, 
consisting of four or five delicate short lamellae on each side. 
Body covered with minute, hardly imbricate, cycloid scales, 
about 4 V by of an inch respectively in the shortest and 
longest diameters. The lateral line traverses the middle of 
the body uninterruptedly. 
The dorsal fin begins slightly in advance of the posterior 
fourth of the body measured without the caudal ; the length 
of its base is shorter than the snout ; its rays, like those of 
the anal, increase gradually in length from before backwards, 
the longest being not quite equal to the major diameter of the 
bulbus oculus. The anal begins an eye-length behind the 
vertical through the middle of the body as above limited, and 
ends a short distance behind the vertical through the poste- 
rior limit of the dorsal ; its longest rays slightly exceed the 
longest dorsal rays. Caudal symmetrically forked, its rudi- 
mentary rays very numerous, both dorsally and ventrally. 
Pectorals narrow, rather more than \ of the head in length. 
Yentrals short, arising immediately behind the vertical 
through the middle of the body, as above limited, and 
reaching just behind the vent. 
