95 



Gill-openings wide : opei'culum with a feeble flat spine. Eiglit branclii- 

 ostegals. No pseudobrancliiaj. 



Dorsal and anal fins confluent with the caudal. 

 No ventral fins. 



A small air-bladder present. Pyloric appendages few and small. 



The curious Halosaurus-like lateral line and the absence of ventral fins and 

 pseudobranchias distinguish this genus from GhjptopMdium, which it otherwise 

 closely resembles. 



Key to the species of the genus Lamprogrammus. 



I. The angle of the preoperculum is simply uotclied ... ... ... L. niqer. 



II. Three weak flat teeth at the angle of the preoperculum ... ... L. frag His. 



74. LamprograDiDius iiiger, Alcock. 



Lamprogrammus niger, Alcock, Ann. Mag. Nat. Hist., Jaly 1891, p. 33, fig. 2 : Illustrations of the Zoology 



OF THE InVESTIGATOK, FISHES, PL. I. FIG. 2. 



D. cirr. 110. A. circ. 90. P. 17. V. 0. 



Length of the head about one-fifth of the total, greatest body height (at 

 the shoulder) equal to the length of the head without the snout. 



Length of the snout about twice that of the eye, less thau the "width of the 

 convex interorbital space. 



The major diameter of the eye is an eighth or a uiuth the leno-th of the 

 head. 



The upper jaw, the length of which is half that of the head, overlaps the 

 lower. Villiform teeth in a broad band in the upper jaW, in a narrow band on 

 the lower jaw and on each palatine, and in a narrow broken A-shaped band on 

 the vomer. 



Angle of the preoperculum notched, the angles of the notch rounded ofp. 

 About ten long gill-rakers on the outer side of the first branchial arch. 



Body and head covered with deciduous, almost membranaceous, scales of 

 moderate size. 



The scales of the very conspicuous lateral line are adherent and greatly 

 enlarged ; they He beneath a continuous sheath of black skin, which is loopholed 

 over a long narrow groove with raised margins situated along the vertical 

 diameter of each scale. These grooves are filled mth an opaque white substance 

 which probably has a luminous function. The lateral line, in fact, is exactly 

 similar to that of several species of Halosaurus. 



