16 



RIBAND-SHAPED. 



was dried and partly defective, the relative dimensions and 

 the number of the dorsal rays nevertheless agree. Some dif- 

 ference between the short description of M. Valenciennes 

 and that which follows, will be pointed out hereafter. 



The body of the Vaagmaer is compressed, or sword-blade 

 like throughout, more than half of its whole length, or, in 

 the present specimen, from the occiput to within eleven 

 inches of the caudal extremity of the dorsal column ; the 

 height is nearly the same at both extremities, and only one 

 seventh part less than the height at the central part of the 

 body, where it is greatest. In this particular it differs from 

 the two species from the Mediterranean, with more than 

 one hundred and sixty dorsal rays, according to their dimen- 

 sions given by M. Valenciennes, — namely, those of Tra- 

 chypterus Jalx, and Tr. iris, a difference distinctly shown, 

 particularly in the latter species. In those two species the 

 greatest height is at, or near, the occiput, from whence it 

 more or less rapidly decreases towards the caudal fin. Of 

 the Tr. leiopterus I am uncertain, as the author has given 

 no dimensions of the height, although he elsewhere states 

 that this species has a caudal fin much thinner than that of 

 the Vagmarus. 



The colour of the head and body is silvery, varied only 

 by the blackish grey of the head, and by two obliquely oval 

 spots of the same colour on each side. The long dorsal fin, 

 and the almost vertical triangular caudal fin, are of a light 

 red. The silvery colour arises from a thin layer on the 

 epidermis, of the same nature as that of the ventral mem- 

 brane observed in several other fishes. I have not been able 

 to observe any traces of scales. The skin underneath the 

 silvery cover is divided or furrowed by diagonal lines, form- 

 ing small flat elevations, some of which are round, and others 

 angvdar. Towards the abdominal margin, particularly on 

 each side of the sharp edge, these elevations a])pear as papil- 



