386 SCOMBEID^:. 



9. HYPSIPTERA. 



Body oblong, compressed, apparently naked, but covered with 

 extremely minute scales ; snout obtuse ; cleft of the mouth of mode- 

 rate width. Opercles not armed. The first dorsal continuous, with 

 very feeble spines ; the second and the anal are much more developed ; 

 finlets none ; anal spines none ; ventrals jugular, composed of three 

 or four thread-like rays. Minute teeth in the jaws. Branchiostegals 

 seven ; aii'- bladder none. Pyloric appendages in small number. 



Open sea. 



1. Hypsiptera argentea. 



B. 7. D. 6-10 I 50. A. 55. V. 3-4. 



Silvery ; back grejnsh-green ; fins transparent. 



a, b. Open sea. Presented by J. B. Godfrey, Esq. 

 o-g. Open sea. Presented by J. B. Godfrey, Esq. 



Description. — The discoveiy of this genus is one of the most in- 

 teresting additions to our ichthyological knowledge, as, although 

 having an entirely Scomberoid aspect, it deviates from this family in 

 having jugular ventral fins. By this character the fish may be 

 readily recognized, even if the specimens are young and several of 

 the characters mentioned should change with age. 



The body is compressed and oblong, its greatest depth, below the 

 spinous dorsal, being contained foui" times and four-fifths in the total 

 length ; the head has the upper surface smooth and flat, and the 

 width of the interorbital space is nearly equal to the diameter of the 

 eye ; the length of the head is contained four times and one-third 

 in the total. The snout is rather short, obtuse, rounded, with the 

 upper jaw overlapping the lower. The cleft of the mouth is of mode- 

 rate width, the maxillary extending slightly beyond the vertical from 

 the centre of the eye. The jaws are armed with minute teeth, but 

 the vomer appears to be toothless. The eye is of moderate size, 

 situated immediately below the upper profile of the head, much 

 nearer to the snout than to the end of the operculum. Belly rounded. 

 The rays of the fins are of an extremely delicate structure, so that it 

 is very diflicult to ascertain theii' number. The spinous dorsal com- 

 mences immediately behind the vertical from the root of the pectoral, 

 and is composed of six spines in the largest of the specimens, whilst 

 the spines are in greater number, short, and filament-like in the 

 smaller ones. Caudal short, subtnmcated. The anal commences 

 behind the origin of the dorsal, and, like the dorsal, it is rather low. 

 The pectorals are of moderate length, and situated high up the sides, 

 on a level with the upper half of the eye. The ventrals, although 

 jugular, are placed laterally, and composed of three long thread-like 

 rays, and there is sometimes a short, inferior fourth. The lateral 

 line is not continued on the tail. 



Unes. 



Total length 24 



Height of the body ^ 5 



Length of the head 5-| 



of the ventral fiai 6 



