New Type of Fishes allied to Nemophis. 139 



flat, and the back ancFbelly rounded ; anus near the end of the ante- 

 rior fourth of the length. 



Lateral line a simple groove, high up and on the side of the back, 

 not continued to the caudal. • 



Head oblong quadrate, transversely convex above and behind ; the 

 forehead slightly declivous, the snout projecting and convex in front, 

 but obliquely truncated below and flattened towards the mouth ; the 

 sides compressed and the lower surface quite plane. 



Eyes moderate, circular, intersecting the profile and mostly in the 

 anterior half of the head. Suborbital chain complete, narrow in front, 

 widest below, with its surface corrugated. Opercular apparatus com- 

 plete ; preoperculum very oblique ; operculum high, nearly rectangulate- 

 triangular, ending in the " opercular angle," and with the base or upper 

 portion concealed under the skin by which it is attached to the 

 shoulder; inter operculum moderate; suboperculum below and behind 

 the operculum, and narrowed towards the angle of the latter. 



Mouth inferior, in front of the eyes, with the cleft sliallow, and the ante- 

 rior or dentigerous margin of the jaws transverse and perfectly straight ; 

 jaivs above immovable and undistinguishable without dissection ; lower 

 jaw nearly flat and very wide, expanded and thinner towards the front, 

 which is perfectly rectilinear transversely. Gape very wide, the lower 

 jaw, which, when closed, shuts obliquely upwards, being capable of 

 retraction even behind the vertical. Intramaxillar veil well developed. 

 Tongue small, far within the mouth. 



Teeth only on the transverse portion of the jaws, uniserial, inserted 

 on the external surface, sigmoidally curved, chiefly compressed trans- 

 versely to the jaws, but with the tips projecting beyond the edge, com- 

 pressed even with the jaws and forming a continuous incisorial edge ; in 

 the lower jaw, on each side of the series of small teeth, a very large curved 

 canine is developed, which is received in a preocular fossa of the palate. 



Bronchial apertures minute, placed far up behind the opercu- 

 lum. 



Branchiostegal rays six, well developed, the outer laminar. 



Dorsal fin continuous from nape above preoperculum nearly to the 

 caudal fin, with its anterior rays slender,, inarticulated spines, and its 

 posterior simply articulated rays. 



Anal fin continuous from the anal region nearly to the caudal. 



MAY, 1865. 11 Ann. Ltc. Nat. Hist., Vol. VIIL 



