4") 2 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



29' W. Ion., at a depth of 88 fathoms. Two additional specimens (Cat. No. 37831 U. S. Nat. 

 Mus.) were secured by the same vessel from station 2407, in 28° 47' 30" N. lat., 84° 37' W. 

 Ion., at a depth of 24 fathoms. The examples obtained are all from the Gulf of Mexico, 

 between the delta of the Mississippi River and Cedar Keys, Florida. 



MONOLENE, Goode. 



Monolene, Goode, Proc. U. S. Nat. Mus., m, sig. 22, Nov. :':;, 1880, 338.— Goode and Bean, Bull. Mus. Comp. 



Zool., x, 194. — Jordan and Gilbert, Hull., xvi, 1*. S. Nat. Mus., 840. — GCnther, Challenger Report, 



xxn. 1887, 165. 

 Thyris, Goode, Proc. V. S. Nat. Mus., m, 344, Nov. 23, 1880 (based on young). 

 Dtluthyris, Goode, Proc 1'. S. Nat. Mus., vn, 1884, 143.— GOnther, Challenger Report, xxn, 1887, 1(10, note. 



Pleuronectoids with thin elongate body and sessile caudal fin. Eyes upon left side very 

 close together, and near to profile. Mouth moderate; the length of the maxillary less than 

 one-third that of the head. Teeth minute in the jaws, in single series, nearly equal on 

 both sides, though perhaps a trifle stronger on the blind side; absent on vomer and pala- 

 tines. Pectoral tin upon blind side totally absent. Dorsal fin commences in advance of 

 the eye upon the snout. Dorsal and anal rays simple. Caudal lin sessile, almost confluent 

 with dorsal and anal. Ventrals normal. Scales rather large, ctenoid upon colored side, 

 cycloid upon blind side. Lateral line marked; on colored side strongly and angularly 

 curved above the anterior two-thirds of the pectoral; on the blind side straight, rising 

 slightly as it approaches the region of the gill opening. Gill rakers few, feeble. Ver- 

 tebra'. 43. 



MONOLENE SESSILICAUDA, Goode. (Figures 357, A and B.) 



Monolene sessilicauda, Goode, Proc. 1'. S. Nat. Mus., in. sig. 22, Nov. 2:>, 1SS0, ::::.-»; Hud, 172. — Jordan and 



Gilbert, Bull, xvi, V. S. Nat, Mus., 841.— Gunther, Challenger Report, xxn, 1887, 165. 

 Thyris pellucidus, Goode, Proc. I'. S. Nat. Mus., in, 1880, 344 (young specimen). 

 Delothyris pellucidus, Goode, ibid, vn, 1884, 143. 



The height of the body (38) is about three-eighths of the total length (without caudal), 

 and is equal to twice the distance of the origin of the ventral from the snout (19); its height 

 over the ventrals (25) is about five times the longitudinal diameter of the lower eye (5), the 

 least height (8.5), at the base of the tail, slightly greater than the length of the lower jaw 

 (8). Body thin, its greatest width (5) not exceeding the longitudinal diameter of the orbit. 



Scales subcircular, with irregular outline, about 2 millimeters in diameter, or about 

 one-fourth (1.25) the diameter of the eye. The posterior edge of each of the scales upon 

 the colored side is pectinate with about fifteen denticulations. The scales of the blind side 

 are oval, nonpectinate, about as large as those of the colored side. The head is everywhere 

 closely thatched with scales, even to the edges of the lips, and small scales occur on the 

 bases of the caudal, pectoral, and ventral tins, and upon the rays of the vertical fins nearly 

 out to their tips. There are about 23 rows above and 25 below the lateral line on the col- 

 ored side, behind the curve of the line. 



Lateral line of colored side strongly bent in its anterior part over the base, and anterior 

 two-thirds of the pectoral fin. There are about 92 scales in the lateral line, 72 of them in 

 its straight portion. The arc of the curved portion of the lateral line (12) is slightly more 

 than double the distance of its highest portion above the line of the straight portion of the, 

 line were it continued (5). The curve of the line is very peculiar, having two angles, that 

 nearest the head being more obtuse. The lateral line ou the blind side is nearly straight, 

 slightly ascending above the abdominal cavity. 



The length of the head (20) equals one-fifth of the standard length, and four times 

 diameter of eye, or length of operculum (5). Distance from snout to margin of upper eye (5) 

 much greater than distance to lower eye (3), and less thau length of the maxillary (5.5), the 

 posterior margin of which passes the perpendicular from the anterior margin of the lower 

 eye. The width of the iuterorbital area is very small, less thau one-sixth of the diameter of 

 the eye. The length of the mandible (8) is two-fifths of the head. 



