2744 Bulletin //, United States National Museum. 



largest upon the trunk, where they are arranged approximately in about 

 4 irregular longitiuliiial rows upon each side of the dorsal fin; closely set 

 rows of these stout spines mark the outer margin of the disk, and there is 

 also a cluster of 5 to 7 upon each carpal peduncle ; outside of these mar- 

 ginal spines, upon each side, is an irregular marginal row of 5 depressed 

 knife-like spines, each tipped with a crown of 3 acicular spinelets; on 

 the anterior margin of the disk the 2 rows coalesce to a greater or less 

 extent and form a bristling array of closely set spines, some pointing dor- 

 sally, some laterally, some ventrally ; 2 kinds of spines upon the dorsal 

 surface, in addition to the large ones alieady described, some large, some- 

 what remote from each other, conical, stellular; others, much more numer- 

 ous and filling the interspaces, pickle-like, stellular; belly armed with 

 numerous closely-set spines of a similar kind ; snout somewhat projecting, 

 armed with 3 many-tipped spines; a spine-armed ridge in front of the 

 eyes, over the top of the snout ; in this 4 spines are conspicuous, 1 in front 

 of each eye, and between these a larger pair in front of the supraorbital 

 ridges; from these last mentioned spines extend spine-armed ridges along 

 the upper margins of each orbit; under the snout is a cavity (horizontal 

 diameter \ that of the orbit) containing a barbel, pediceled, with thick, 

 club-shaped, trilobate tip; on each side of this cavity are the nasal open- 

 ings, which are as in HaUeutichthya. Width of mouth eriual to distance 

 between centers of pupils of eyes. Diameter of orbit contained as follows 

 in other dimensions of the body: In total length 9.^; in distance from 

 snout to dorsal 6; same to anal 7; the base of ventrals 3; to angle be- 

 tween pectorals and trunk 5^; to gill openings 5; in greatest width of 

 disk 5^; of trunk 4. Width of iuterorbital area in diameter of orbit f. 

 Dorsal fin with 6 or 7 rays, the longest (third) 1^ times diameter of orbit 

 and 6 times in total length; anal fin inserted entirely behind dorsal, with 

 4 rays, the longest (third) about as long as longest in dorsal fin; ventral 

 fins inserted nearly under middle of disk, a little nearer vent than to 

 mandibular symphysis, with 1 rudimentary and 5 well-developed rays, 

 increasing in length posteriorly, the last and longest 6^ times in total ; dis- 

 tance between ventral organs 7^ in total length. Pectorals with pedun- 

 <les slightly exseited, bases included in common membrane, composed of 

 13 to 15 rays, the longest third or fourth 4i| in total. Caudal fin rounded, 

 consisting of 9 rays, all bifid except the 2 external ones ; length of middle ray 

 about i that of trunk and exceeding that of pectoral, being contained 4^ 

 times in total length. Stomach egg-shaped, intestine somewhat longer 

 than body ; liver very wide and large. Color uniform reddish, gray above, 

 slightly lighter below. Deep waters of the Atlantic; very abundant, in 

 about 300 fathoms. Known from the west coast of Africa, ofl:' the Cape 

 Verdes, off" Barbados, and north in the Gulf Stream to Newport, {atlan- 

 ticus, of the Atlantic.) 



Dibranchiis atlanticus, Peters, Monatsber. Kon. Akad. "Wiss. Berlin 1876, 736, ■with plate. 

 West Africa, Lat. lo'^ N., Long. 17° W., in 360 fathoms (Coll. H. M. S. Gazelle) ; GUN- 

 THER, Challenger Keport, xxii, 59, 1887; Vauxant, Travailleur, etc., 343, 1888; Goode &, 

 Bean, Oceanic Ichthyology, 501, pi. 122, fig. 413, 1896. 



