THE LANTERN FISHES. 227 



ventrals ; ventrals overlapping front of anal, their insertion under the first 

 rays of the dorsal ; origin of anal under last dorsal rays ; front of adipose 

 fin vertically above last anal ray. 



Scales and much of the epidermis lost, but the ground color evidently 

 dark brown or blackish. An evident pigment line dividing the photophores. 

 A minute round photophore, smaller than any of the others, on the anterior 

 upper margin of the orbit immediately above the nostril, under the anterior 

 projecting rim of the supraorbital portion of the frontal. A similar minute 

 photophore is frequently present in this exact location in many species of 

 Diajjkus and Myctophum, and is frequently to be recognized as distinct from 

 the large preocular luminous area, where this is present in Diaphiis. In 

 D. urolampiis, this minute photophore is represented by a densely pigmented 

 black globular body, apparently no longer functional. 



Supra-pectoral photophore slightly nearer lateral line than base of pectoral, 

 without the glandular body usually associated with it in this genus ; the two 

 infra-pectorals forming with the first thoracic a straight, obliquely ascending 

 line, the spots evenly spaced ; first pair of thoracics separated from second 

 pair by a wide interval, about twice the length of the space separating the 

 second pair from the third and the thii'd from the fifth ; fourth pair elevated 

 as usual, above and slightly behind the third pair ; first three ventrals form- 

 ing an obliquely ascending line, the second more widely separated from the 

 third than from the first ; distance between upper and middle supra-anals 

 more than twice that between the middle and lower ; lower supra-anal very 

 near the fifth ventral and a little behind it; antero-anals 7 or 8 in number, 

 the first above and slightly in front of the second, the line joining the two 

 traversing the lateral line slightly behind the upper supra-anal ; last antero- 

 anal also elevated, above and behind the next to the last, the line joining 

 the two passing behind the postero-lateral ; all antero-anals, except the first 

 and last, in a straight line parallel with the base of the anal fin; postero- 

 anals 4 or 5 in number ; precaudals 4, equally spaced, following the curve 

 of the base of the fin ; upper supra-anal and the postero-lateral immediately 

 below the lateral line, the upper precaudal somewhat more distant from it, 

 the supra-ventral very slightly nearer lateral line than base of ventrals. 

 Two small specimens secured at Ilydrographic Station 3798 (A. A. 27). 



