THE LANTERN FISHES. 229 



evidently blackish, the bases of the vertical fins black. Dorsal, anal, and 

 caudal fins with the articulations of the rays finely dotted with black, the 

 fins thus with fine wavy cross-lines, which are especially noticeable on 

 the caudal. Two broad dark bars cross the mandibles, one below the 

 posterior part of eye, the other immediately in front of mandibular joint. 



Preocular luminous organ occupying the space between the eye and 

 the nostril, extending but little above or below the latter, not extending 

 on the suborbital region. Its anterior margin is deeply indented opposite 

 the nostril, but there is no evident division into an upper and a lower 

 portion. At its upper margin, but separated from it, is a minute round 

 photopore surrounded with pigment, as in D. acjassizii. No subocular spot, 

 the anterior half of suborbital region bright silvery. Supra-pectoral slightly 

 nearer the lateral line than the pectoral fin, there being associated with it a 

 whitish glandular organ, as in nearly all species of this genus. Lower 

 infra-pectoral spot midway between upper infra-pectoral and first thoracic. 

 First and second thoracics widely separated, the third midway between 

 second and fifth ; fourth thoracic elevated as usual in the genus, a little 

 higher than the base of the ventral fins, and slightly behind the third 

 thoracic. Second and third ventral photophores progressively elevated, 

 as usual, the third slightly in front of the vertical from the fourth and 

 below the direct line joining the first and second ; the second is much 

 nearer the first than the third. First antero-anal elevated, slightly in 

 advance of the second, which is widely separated from the third ; third 

 to sixth antero-anals equally spaced and less widely separated, the third, 

 fourth, and fifth almost equally distant from base of anal, the sixth dis- 

 tinctly elevated, but less so than the first. Postero-anals four in nmnber 

 (five in sphndidm), the last separated by a wide interval from the first 

 precaudal, which is in.serted distinctly in advance of the rudimentary caudal 

 rays. Distance from supr.a-ventral spot to lateral line two-thirds its distance 

 from ventral fins. The upper supra-anal, the postero-lateral, and the upper 

 precaudal encroach on the scales of the lateral line. Supra-anals slightly 

 angulated, the lower two forming with the fifth ventral an obliquely 

 ascending straight line, which intersect the lateral line behind the upper 

 supra-anal. 



