408 DEEP-SEA FISHES OF THE ATLANTIC BASIN. 



Tliis species belongs in tliesnbs'eiuis Kematontiriis of Giiwthor. It resembles }fiicrn)us 

 (iffniis, from wliicli it diiVers in its smaller eye (one lifth iis long as the liea<l),aiul in having 

 the head contained 5| times in the total length, instead of 5 times as in affinis. 



The Blair secnred specimens from station cccviii, in 41° 25' 45" N. lat., 65° 35 30" W. 

 Ion., at a depth of 1,242 fathoms; from station cccix, iu 40° 11' 40" N. lat., dS'^ 22' W. Ion., 

 at a depth of 304 fathoms; and from station lxxvi, off Havana, at a depth of 154 fathoms. 

 The Albatro.ss also obtained examples fi'om station 25G4, in 39^ 22' N. lat., 71° 23' 30" W. 

 Ion., at a depth 1,390 fathoms; from station 2503, iu 39° IS' .30" N. lat., 71° 23' 30" W. Ion., 

 at a depth of 1,422 fathoms; from station 2534, iu 40° 01' N. lat., 67° 29' 15" W. lou., at a 

 depth of 1,234 fathoms; from station 2502, in 39'= 15' 30" N. lat., 71° 25' W. lou., at a depth 

 of 1,434 fathoms; Gat. No. 33392, U. S. N. M., from station 2074, in 41° 43' N. lat., G5^ 21' 

 50" W. Ion., at a depth of 1,309 fathoms; Cat. Nos. 33274 and 33276, 11. S. JST. M., from sta- 

 tion 2035, in 39° 20' IG" N. lat., 70° 02' 37" W. Ion., at a depth of 1,309 fathoms; Cat. No. 

 33302, U. S. N. M., from station 2041, iu 39° 22' 50" N. lat., 08° 25' W. lou., at a depth of 

 1,608 fathoms. 



HYMENOCEPHALUS CAVERNOSUS, Goor.K aiid Bean. (Figure 341.) 



Batlujgudus carertiosus, GooDK auil Bean, Pioc. U. S. Nat. Mus., 1885, 508. — GiJNTHER, Challenger Report, 

 XXII, 1887, 156. 



Body stoutish, its greatest height (23 millimeters) contained 7 times in total length. 



The scales are moderate, deciduous, cycloid, with no visible armature, about 8 rows 

 under the base of the first dorsal. 



Length of head (28 millimeters) about 6 in total length. The bones of the head are 

 very soft and cavernous, iu many places without muscular covering, spongy. luterorbital 

 area doubly concave with a spinous medial ridge; its greatest width (10 millimeters) about 

 24 iu the length of the head. 



Postorbital portion of head (13 millimeters) about half its length, IJ as long as eye, 

 which is circular, its diameter (10 millimeters) contained 2i times in the length of the liead. 



Snout broad, very obtuse, its width at nostril nearly equal to interorbital width, its 

 length (6 millimeters) 4'^ times iu that of the head. Nostrils normal. 



Teeth in both jaws iu villiform bauds, very small; a naked space at the symphysis of 

 of the intermaxillary^ vomer and palatine toothless. Gill-rakers very short, minute, and 

 rather numerous; about 18 below the angle of the anterior arch. Pseudobrauchia' absent. 

 Barbel two fifths as long as the eye. 



First dorsal composed of 2 spines, the first of which is minute, inserted at a distauce 

 from the snout (28 millimeters) equal to the length of the head; the second as long as the 

 head without the snout, and 10 branched rays; its base (10 millimeters) equal to diameter 

 of eye. Second dorsal almost rudimentary, its rays remarkably short, about 133 in num- 

 ber; its distauce from the first dorsal half the length of head. 



Anal much higher than second dorsal, its distance from the snout (46 millimeters) con- 

 tained about 3i times iu the total length. About 27 rays iu a space equal to length of 

 head. Anterior rays longest, in length about three fourths of the diameter of the e.ye. 



Pectoral inserted under the first branched ray of the first dorsal, its length (20 niilli 

 meters) equal to twice that of the eye and about two-thirds length of head. 



Ventral slightly behind the pectoral, its first ray filamentous, reaching to the base of 

 the tenth anal ray; it consists of 11 rays. 



Color, gray, with silvery tints on sides; the abdomen and lips dark. 



Dr. Bean has rel'xamined the tyi)es of Batkyijadus camiiosns, and is convinced that 

 Dr. Giiuther is probably right in his statement that it belongs to the subgenus MyxUi- 

 co)iunis, but since the specimens nrv all young and have more rays in the ventral fin 

 than the described species, it can not be referred to M. louf/ifilis, and must be called for the 

 present Hymcnoceplmlus cavcrnosus. 



The following revised data are presented: 1). ii, 10, 133; A. 27 rays in space equal to 



