4 Messrs. Hancock and Embleton on a Gymnetrus 
in the neighbourhood of the head by irregular depressed indu- 
rations of the skin. 
The head is small and short, measuring 9 in. from the snout 
to the posterior margin of the gill-cover ; the outline of the lower 
jaw is a wide arch convex below, and stretching forwards and 
upwards to the mouth, which is placed in an elevated position 
and opens upwards and forwards ; the mouth is small, nearly cir- 
cular, and capable of being projected 2 or 3 in. forwards when 
the lower jaw is depressed. The profile of the head from the 
anterior end of the crest is at first suddenly concave, the conca- 
vity facing forwards and upwards, and just behind the anterior 
end of the curve exists the nasal chamber which is small, and 
owing to the damaged state of the fish we could only find one 
small aperture, which was longer than it was broad. Beyond this 
concavity the premaxillary bones project nearly horizontally to 
the mouth. The eye is 14 in. in diameter, the iris of a beautiful 
silvery white, and rather broader than the diameter of the pupil. 
The eye is situated 2} in. below the base of the crest and 13 in. 
behind the frontal concave profile. There is a narrow imperfect 
circle of a dusky colour round the contour of the eyeball. The 
eye is very flat. The tongue is rather promment, but small, 
smooth and fixed. There are no teeth. The interior of the mouth 
is black. 
The gill-covers are large in proportion to the size of the head, 
prolonged backwards, their posterior angles considerably ele- 
vated. The preoperculum has somewhat of a crescentic form, 
the lower border convex ; the anterior horn is narrow and pro- 
longed to its articulation with the lower maxilla, the posterior 
border has an obtuse angle pointing backwards. This border 
corresponds to and may rest upon the edge of the concavity 
formed by the operculum above and the interoperculum below. 
The operculum is on the whole broad and irregularly quadrate, 
with the upper anterior angle prolonged forwards and upwards ; 
the upper margin is smooth and slightly concave nearly as far as 
the angle, it then curves suddenly downwards a little to the 
angle which is rather obtuse. Below this is the posterior border, 
which is somewhat sinuous and rather oblique from above down- 
wards and forwards. 
The inferior border is nearly straight, and directed upwards 
and forwards corresponding to the interoperculum. 
The remaining bone, which we take for the interoperculum, is 
narrow and thin, prolonged almost to a point under the jaw and 
widening gradually to its posterior end, which is rounded and 
projects backwards beyond the preoperculum. Its lower border 
is convex aud lies almost horizontally. 
_ These are the only pieces observed as entering into the forma- 
