182 



This species is distinguished from X. socialis by the prominent scaly lateral 

 line and by the much fewer rays in the dorsal and anal fins. 



Leptoderma, Vaillant. 



Leptoderma, Vaillant, Exp. Sci. Travaillenr et Talisman, Poiss. p. 165 : Goode and Bean, Oceanic Ichthyology, 

 p. 18. 



Body low, very elongate, tail tapering almost to a filament ; skin naked. 

 Head moderate, with enormous eyes. Cleft of the mouth small, the edge of the 

 upper jaw formed nearly equally by the premaxilla and maxilla. A series of 

 small teeth in both jaws, none on the palate. 



Gill-opening wide but not reaching much above the level of the pectorals, 

 the upper arc of the gill-arches also truncated. Numerous close-set lanceolate 

 gill-rakers. Pseudobranchia? present, small. 



Dorsal and anal very long, ending near the caudal, the anal the longer. 

 Caudal very small, forked. Pectorals and ventrals well developed. 



Distribution : Atlantic coast of Morocco ; Bay of Bengal. 



145. Leptoderma affinis, n. sp. 



Leptoderma macrops, Alcock, Ann. Mag. Nat. Hist. (6) X. 1892, p. 361, (an Vaillant ?) : Illustrations of the 

 Zoology of the Investigator, Fishes, pl. XXXII. fig. 3. 



D. circ. 66. A. circ. 85. V. 5. 



Greatest height of the body, at the shoulder, about half the length of the 

 head, which is about two-ninths of the total. 



Eye-ball considerably more than a third the length of the head and nearly 

 twice as long as the snout. 



The snout is squarish ; the mouth is terminal, much as in Aulastomomorpha, 

 the maxilla being vertical when the mouth is opened in a perfectly natural 

 manner. The maxilla is very broad and consists of three pieces. The rami of 

 the mandible are also of great breadth, except anteriorly where there is a series 

 of small teeth. A series of small teeth on the premaxilla ; none on the maxilla 

 or palate. 



The anal begins an eye-length nearer to the snout than to the base of the 

 caudal fin ; the dorsal begins about half a head-length behind the first anal ray : 

 both fins extend nearly to the caudal. The distance of the ventrals from the 

 <rill-opcning is equal to the length of the head without the snout. 



The skin is naked and intensely black. In life it is uniformly covered with 

 a thick velvety opalescent epidermis which is probably luminous in function. 

 The lateral line, which consists of a row of pores, extends from the occiput to 

 the caudal. 



