156 



DEEP-SEA FISHES OP THE ATLANTIC BASIN. 



The vent is placed a little farther back thau in the typical species of the genus; the 

 length of the tail, compared to the total length, is in that more than ten-elevenths and 

 only seven-ninths in the individual here described. The skin being for the greater part re- 

 moved, together with a portion of the iins, some important characters are wanting. I find 

 no trace of the dorsal, exc('])t an incomplete ray, which is a little behind the anus; the anal 

 commences immediately behind this last. It appears to have been higher than the dorsal. 

 The base, moreover, of the scai)ular bone, which supports the pectorals, alone enables us to 

 determine the location of these fins behind the branchial aperture. 



Measurements {given by M. Vaillanl). 



Leligtli of body... 

 Height of body . . . 

 Thickness of body 

 Length of head . . . 

 Tengthof tail.... 

 Length of snont . . 

 Diameter of eye . . 

 Interorl)ital spaee 



Millimeters. Hundredths, 



We find the principal character given to this species by Dr. Vaillant to be the 

 insertion of the anus at a distance from tlie pectorals double that which separates the 

 pectorals from the eye. As for the proportional elongation of the body, which is greater 

 in till' N't'michthi/fi scolopaceiis, Tiicliards(ni, than in Nemichthys iufana, Giinther, in our exam- 

 ple the ditterence is less nnirked. 



Serrivomer Richardii is represented as having the eye one twenty-fifth of the length of 

 the head; in S. Bcanii the eye is much larger, forming more than one-twentieth of the 

 length of the head. In S. Rkhardii the origin of tlie dorsal fin, if correctly represented, 

 is distant from the gill-opening a space nearly equal to the length of the head, while in S. 

 lieanii its distance from this point equals the length of the head. The gape of the mouth 

 also in S. Richardii is api)arently much wider than in 8. Beanii, the angle of the mouth 

 being well behind the vertical through the eye in 8. Richardi and below the posterior mar 

 gin of the eye in S. Beanii. 



Serrivomer Richardii was taken at station 131 of the Talisman, off the Azores, at a 

 depth of 2,995 meters. 



GAVIALICEPS, Wood-Mason. 



Gavialicepa, Wood-Mason, with Alcock, Ann. and Mag. N:it. Hist., 1889, 460. . 



Body elongate, compressed, with long, lash-like tail. Head depressed, and snout a spat- 

 ulate or uecdle-like beak. Teeth small, sharp, in a double row in each jaw. Vomerine 

 teeth larger. Gill openings separate but I'eaching nearly to middle line of abdomen. Vent 

 somewhat remote from throat. No pectorals. 



Two species are known from the Bayof Bengal, viz: (J. ta'niola, Wood-Mason, 265 fath- 

 omo, and G. microj)s, Alcock, 1,045 fathoms. 



Order LYOMERI. 



Lyomeri, Oii.i. and Rydki:, I'ron. U. S. Nat. Mus., \ i, 1883, 263. 



Fishes with five or six branchial arches (none modified as branch iostegaj or pharyngeal) 

 far behind the skull; an imperfectly ossitied cranium deficient especially in nasal and vom- 

 erine elements articulating with the first vertebra by a basioccipital condyle alone; only 

 two cephalic^ arches, l)oth freely movable, (1) an anterior dentigenms one, and (2) the sns- 

 peusorial, consisting of tlie hyomandibiilar and quadrate bones, without opercular elements; 

 the scapular arch, imperfect{limited to a single cartilaginous plate), remote from the skull, 

 and with separately ossified, but imperfect vertebrae. (Gill.) 



