DISCUSSION OF SPECIES AND THEIR DISTRIBUTION. 323 



being developed. The palatine baud is broader thau the mandibulary, aud the vomeriue 

 baud A-«haped, each arm being bent with the convexity inwards. 



Gill-opening aud cavity very wide and of an intense black. The gill-rakers are much 

 longer thau the laminis, 15 in number on the anterior arch, besides some rudimentary ones 

 above. 



The dorsal fin commences above the upper end of the gill-opening, with short rays 

 partly hidden in the skin; the rays become longer in the middle of the flu, but remain of 

 moderate length, and the anal rays are still shorter. The pectoral has a rather narrow 

 base, is quite free, and comi^osed of feeble rays ; its length is only half that of the head. 

 Ventral rays very feeble, reaching somewhat beyond the root of the pectoral. 



Only very few of the thiu, cycloid, scales have been preserved ; they are of moderate 

 size, there being about sixteen in a transverse series running from the vent to the dorsal fin. 

 The lateral line, if it was developed, can no longer be traced. 



Radial formula : D. 16U; A. 92; P. 23; V. 1. Color, blackish, with the fins, head, and 

 abdomen black. (Gilnther.) 



The species was obtained by the Challeiu/cr from the mid-Atlantic in 1,500 fathoms 

 (station 107), aud also from the Philippines (station 205), at a dejith of 1,050 fathoms. 



BASSOZETUS T.ENIA, (Gunthee), Goode ami Bean. 

 Bathyoniis twnia, Gunther, Challonger Report, xxii, 1887, 110, PI. xxiii, Fig. A. 



The greatest depth of the body is below the origin of the dorsal fin and about one-third 

 of the length of the trunk, the vent being not quite thrice as distant from the extremity of 

 the tail as from the snout. Therefore tlie whole fish, and especially the tail, is much 

 attenuated. Head not compressed, low and long, forming four-sevenths of the length of 

 the trunk. Structure of the bones of the head as in Bassozetus compressus. Snout rather 

 swollen and broad, the upper jaw but slightly overlapping the lower. Maxillary extending 

 far behind the eye, which is very small, one-third the length of the snout, about one-four- 

 teenth of that of the head, and oue-fourtli of the width of the interorbital space. AH the 

 teeth are very small and short, densely set, forming narrow villiform bands; vomerine band 

 open, V-shaped. Gill-cavity deep black; gill-rakers long aud slender, sixteen in number, 

 with some rudimentary ones in front and behind. 



The dorsal fin commences above the upper end of the gill-opening, with short rays 

 partly hidden in the skin; the rays become longeron the anterior third of the tail, but 

 remain of moderate length, and the anal rays are still shorter. The pectoral has a broad 

 base, is quite free, and composed of rather feeble rays; its length is equal to that of the 

 postorbital part of the head. Ventral rays very feeble, reaching nearly to the middle of the 

 pectoral. 



The scales must have been extremely thin, and rather small; there are probably about 

 twenty in a transverse series running from the vent to the dorsal fin. The lateral line can 

 not be made out. - 



Eadial formula: D. 138; A. 115; P. 30. 



Light-colored (possibly pink in life), with the head and abdomen black. 



BASSOZETUS CATENA, Goode and Bean. (Figure 286.) 



Bathj/onits catena, Goode and Beau, Proc. U. S. Nat. Mus., viii, 1885,603. — GuNxriEU, Challenger Kei)ort, 

 XXII, 1887, 111. 



Body very elongate, much compressed, and tai)ering into a slender, whip-like tail. Its 

 height (10 millimeters) is contained li times in length of head and 12i times in that of the 

 body. 



Head without spines, very cavernous, not much compressed, higher than body, its 

 length (27 millimeters) contained Sg times in that of body. Interorbital area somewhat 

 convex, its width (measured upon the bone) equal to the diameter of the eye and about 

 equal to that of the snout, and contained 5 times in the length of head. 



