] 72 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



The body and head covered by minute, imbricated scales. A line of mucous pores extends 

 from the anterior end of the lateral line forward under the eye and to the end of the maxilla. 



The dorsal spines are short, distant from one another, the first being over the end of 

 the opercle, the fifth slightly behind the vertical through the origin of the pectoral, the 

 twelfth slightly in advance of theorigin of the pectoral, the fifteenth almost over the origin 

 of the anal, and the last (twenty-eighth) a little behind the middle of the length of the tail. 

 In another individual the fourth spine is immediately over the pectoral insertion, the thir- 

 teenth over the ventral origin, and the whole number of spines is 30, but there is behind 

 the thirtieth a minute spine almost united by membrane. The anal begins immediately 

 behind the vent and after the fifth spine the height of the fin remains uniform until the 

 length of the rays gradually decreases near the tip of the tail. The pectoral is inserted at 

 a distance from the gill opening nearly twice its own length. The ventrals have a broad 

 base, are not confluent, and reach to the vent or slightly beyond it. 



Eadial formula : — D. xxvm-xxxi; A. xlii-liii. 



The types are number 35601, U. S. N. M. , and were obtained by the steamer Albatross 

 at station 2216, K lat. 39° 47', W. Ion. 70° 30' 30", in a depth of 963 fathoms. They meas- 

 ure 16i and 16 inches, respectively. Another specimen, 17 inches long, was obtained by the 

 same steamer at station 2553, N. lat. 39° 48', W. Ion. 70° 36', in a depth of 551 fathoms. 

 The Hirondelle took it off Newfoundland, in 1,267 meters. 



Closely allied to M. rostrata is Xotacanthus challengeri Vaillant (=Xotacanthus Risso- 

 (iii us, Giinther, Challenger Report, xxn, 250, pi. lxi, Fig. B, not Filippi and Verany), re- 

 named by Vaillant in the report of the Travailleur and Talisman, p. 387. This is distin- 

 guished by the larger number of its dorsal rays, the less anterior position of the origin of 

 the dorsal, the lesser height of the body in comparison with the distance from the vent to 

 the snout, comparatively longer snout and larger eye, and the absence of the suborbital row 

 of mucous pores. 



This form was obtained by the Challenger at station 237, south of Yeddo, in 1,875 

 fathoms. 



Dr. Giinther states that although this is a matter of some uncertainty, the diagnosis of 

 H. Rissoanus '-applies sufficiently well to his specimen;" further remarking that ''since a 

 number of Mediterranean fishes are identical with Japanese, and at least one other species 

 of Notacanthus (A. Bonapartii) shows a wide geographical range, he should not feel justi- 

 fied in giving a distinct name to the fish described." We can not help feeling that Dr. 

 (iiiuther has departed from his customary cautious and scientific method in this case, and 

 are satisfied that he would not have done so had he seen the specimen obtained by the 

 French exploring expedition on the coast of Morocco, and described and figured by Vail- 

 lant. Coming, as it does, from the Mediterranean region, and having the proboscis-like 

 character of the snout, much more emphasized than in the Japanese form, the presumptions 

 in favor of its identity with A. Rissoanus are very strong. We therefore not only adopt the 

 identification of Vaillant in preference to that of Giinther, but accept the new name which 

 Vaillant has proposed for the Japanese form. 



Family LIPOGENYID^. 

 IApogenyidce, Gill, MS. 



Heteromes with a roundish, inferior, suctorial mouth ; imperfect lower jaw with its rami 

 separated at middle, connected with the corresponding sides of the upper jaw, and invested 

 in a thick, transversely plicated, horseshoe shaped lip, reflected upwards behind on the 

 cheeks; no teeth; short row of 4 or 5 partially connected graduated dorsal spines and 5 to 

 7 branched rays, forming a regular fin. (Gill.) 



The anomalous and unexampled modification of the lower jaw and mouth deserves a de- 

 tailed anatomical examination, but the existence of only one specimen — for the present, at 

 least; — is deemed to render such an investigation inadvisable. 



