DISCUSSION OF SPECIES AND THEIK DISTRIBUTION. 159 



No traces of ,i lateral line. Veut premcdiaii. Ray« of vertical fins sleuder aud flexible. 

 Tail free, termiuatiiig' in sleuder point. 



EURYl'HAUVNX PELECANOIDES, Vaillant. (Figuri' 17(i.) 



Etirypharynx pctevaiioides, Vaillant, Comptes Rendus Acad. Sc, Paris, xcv, 1226, live. 11, 1882; Y.xyi. Sci. 



Tr.availleur t-t Talisman, lOS, id. xvii.— Cn.L and Ryder, loc cit. 

 Siccopharynxpclevanoida,; (iiNTiiKi:, Cliallcnger Report, xxil, 1S87, 262. 



Bothjaws pos.sess merely feeble dental grauulatious, but the lower jaw is armed in front 

 with a pair of slender curved teeth (2 millimeters long). The length of the Jaws is about 

 one half of tliat of the body. The origin of the dorsal fin is nearer to the end of the snout 

 than to the vent; neither the dorsal nor the anal fin reach the end of the tail (which termi- 

 nates in a small, skinny lobe). Gill-opening a very .small round opening. No bluish-white 

 line along the back. (Giinther.) 



" This animal," writes Gill, "is about 0.47 meter long and 0.02 meter high at the most 

 ele\ated part and is of an intense deep-black color. The body, the form of which is inasked 

 in front by the abnormal mouth, which will be mentioned further on, resembles that of 

 Mavrurus; it becomes regularly attenuated from about the anterior fourth, the point at 

 which the external branchial orifice is seen, and terminates in n point at the caudal extrem- 

 ity ; the anus is situated at the junction of the anterior third with the posterior two-thii-ds 

 of the body. 



" What gives this fish a very peculiar physiognomy is the arrangement of the jaws and 

 the structure of the mouth, which are even an exaggeration of what Mr. Ayres has described 

 in Malacosteus niger. Although the head is .short (scarcely 0.03 meter), the jaws and the 

 suspensorium are excessively elongated; the latter did not measure less than 0.005 meter; 

 and from this it results that the articular angle is carried very far back, to a distance fi'om 

 the end of the muzzle equal to about 3.1 times the length of the cephalic portion." 



GASTROSTOMUS, Gill and Ryder. 

 Gaatrostomus, Gill and Ryder, Proc U. S. N.at. Mas., 1883, vi, 271-273. 



Eurypharyngids with the cranium abbreviated and little or no longer than broad, 

 minute acute conic teeth depressed inward in a very narrow band on the jaws (no en- 

 larged teeth at the extremity of the mandible), aud the tail witli an eradiate membrane 

 under its terminal portion. Gill-opening close to angle of mouth. 



GASTROSTOMUS BAIRDII, Gill and Ryder. (Figures 181,182.) 



Gaatrostomus Bairdii, Gill and Ryder, Proc. U. S. Nat. Mus., 1883, vi, 271. 



The cranium forms about one-thirtieth or less of the extreme length, and is as broad as 

 long; the jaws are excessively elongated, being nearly (in large) or more (in young) than 

 7 times longer than the cranium; there are about 100 rays in the dorsal fin aud about 

 107 in the anal; the pectorals are very small, being only about as long as the diameter of 

 the eye, and little more than twice as long as wide at the base, and have about nine simple 

 rays. The rays of the uupaired fins are quite flexible iu the small individuals, but quite 

 rigid aud more perfectly ossified iu the larger; they become obsolete toward the end of the 

 tail. The rays, which are rigid and well ossified anteriorly, become shorter, very slender, 

 and flexible — in fact, almost as limp as threads near the end of the tail. The vertebral 

 bodies become longer and more attenuated toward the end of the tail. 



Met«r. 



Meter. 



Extreme length 47 



Body : 



Height at branchial region 035 



Height at anus 025 



Cranium : 



Length 015 



Width 015 



Iiitcrorbital area Oil 



Height at commencement of anal lin 02 j Orbit, diameter 003 



Length of abdominal cavity 05 1 



