406 MR. J. Y. JOHNSON ON NEW GENERA OF [NoV. 10, 



inch. 



Dorsal, distance from muzzle 1 1^ 



, length of base 1^ 



Pectorals, length If 



— , distance from muzzle l^ 



Ventrals, distance of their roots from roots of pec- 

 torals 1^ 



Appendage of vertical fins, length -f^ 



, width, rather more than -^ 



Anal, length of base 1 1\^ 



Tail, length xV 



, height T^. 



Caudal fin (mutilated) ,^(y 



Order MALACOPTERYGII. 

 Halosaurtjs, gen. nov. 



Body elongated, clothed with cycloid scales ; belly rounded ; tail 

 compressed and tapering to a point. Snout projecting much beyond 

 the mouth, which is non-protractile and of moderate size, with the 

 upper border formed by the premaxillary and maxillary bones, the 

 former small, the latter of moderate size and not reaching beyond 

 the eye, both dentiferous. Teeth in villiform bands, in the jaws and 

 on the vomer, palatines, and tongue. A short dorsal over the space 

 between the abdominal ventrals and the long anal, which is coales- 

 cent with the caudal, the latter consisting of very few rays. Large 

 gill-openings. Branchiostegal membrane with numerous rays. Sto- 

 mach csecal ; pyloric caeca in moderate number ; a large air-bladder. 



No pseudobranchiae, no barbel nor adipose dorsal. 



Halosaurus ovenii. (PI. XXXVI. fig. 2.) 



D. II. P. 11. V. 10. A. 191! C. 2. M.B. 14. Scales of 

 lateral line about 170. 



Body elongated, compressed, attenuating in both directions from 

 the neighbourhood of the dorsal fin, the tail becoming filiform ; the 

 belly rouiided, except in the neighbourhood of the ventral fins, where 

 it is flattened. Clothed with cycloid scales of a moderate size. The 

 height compared with the total length is as 1 to 14 J. The back and 

 sides are brown, the middle of each scale being bluish grey with mi- 

 nute black dots. The belly is grey. 



The head has something of the aspect of a Macrourus or a Coilia, 

 the mouth being on the under side. Compared with the total length 

 it is as 1 to 7\- It is unarmed, scaly, slender and depressed, with a 

 projecting snout. At the back there is a transverse narrow scaleless 

 groove, which curves forwards slightly. The lateral eye is oval, with 

 an angle before and behind. Compared with the length of the head 

 it is as 1 to 5. It reaches to the profile, and is distant from the snout 

 nearly two of its longer diameters ; and the space between the eyes 

 is less than one of such diameters. The snout is curiously formed ; 



