582 Bulletin 47, United States National Museum. 



Subgenus CYCLOTHONE. 

 873. CYCLOTHONE MICRODON (Glinther). 



Head 4f ; depth 7f ; eye as long as snout, 7 in head. B. 7 to 9 ; D. 11 

 or!2; A. 16to20; C. 17; P. 9orlO; V. 5. Bodyelongate. Cheeksnaked. 

 Premaxillary very short, extending to vertical from posterior limb of 

 anterior nostril ; maxillary very strongly curved downward, with a short 

 knob at its anterior extremity, not visible without dissection. Most of 

 the teeth on maxillary inclined forward. Gill rakers 9+13 or 14. 

 Lower jaw long, included, with the exception of the projecting tip. Eye 

 circular, close to the profile, the interorbital area being very narrow; 

 anal under second ray of dorsal, its base half as long again as that 

 of dorsal, and nearly as long as body; its outline resembling that of 

 dorsal, its longest ray a little longer than the longest of the dorsal ; cau- 

 dal forked; pectoral inserted under tip of opercular flap, its length 

 equal to greatest height of body ; ventral inserted at a distance from 

 snout equal to twice the length of the head, its length slightly exceeding 

 that of the pectoral, 7 in body. Color blackish brown, the luminous 

 pores inconspicuous, in a row on each side from pectoral region to tail, and 

 another below it from throat to the origin of anal. (Goode & Bean.) 



First obtained from great depths near Bermuda, subsequently at numer- 

 ous localities in the Atlantic, Pacific, and Antarctic oceans, at depths of 

 from 500 to 2,900 fathoms. Since also taken from numerous localities in 

 the Atlantic by the Albatross and the Blake. It is equally abundant in 

 deep water along the Pacific Coast from Oregon to the Galapagos . In fact it 

 is everywhere one of the most widely distributed and common of all deep- 

 sea fishes. "Although many hundreds of specimens are in the National 

 Museum, the species is so exceedingly delicate and hard to preserve that 

 not one of them gives satisfactory opportunity for study." (Goode & 

 Bean.) ([impos, small; bdoi>, tooth.) 

 Gonostoma microdon, GUNTHER, Ann. and Mag. Nat. Hist., n, 1878, 188, near Bermuda; GliN- 



THER, Voy. Challenger, xxn, 175, 1887 ; MTKEN, Spolia Atlantica, Scopelini, GO, 1892. 

 Oyclothone lusca, GOODE & BEAN, Bull. Mus. Comp. Zoo'l., x, No. 5, 1883, 221, Gulf Stream. 

 Oyclolhone microdon, GOODE & BEAN, Oceanic Ichthyology, 990, -fig. 114, 1895. 



874. CYCLOTHONE BATHYPHILA (Vaillant). 



Head 4| ; depth 11. D. 12 or 13 ; A. 21 or 22; V. 7; P. 10; branchios- 

 tegals 13. Body elongate, compressed; vent midway between tip of 

 snout and end of caudal rays. Eye moderate, its diameter equal to half 

 length of snout, and also to the width of interorbital space; placed 

 far forward, so that the snout is very short, length of head. Cleft of 

 mouth exceedingly wide, oblique. Maxillary somewhat dilated, but not 

 covering any considerable portion of the cheek, its tip separated from 

 the angle of the operculum by a distance greater than the diameter of 

 the eye. Teeth of premaxillaries moderate in size ; upon maxillaries and 

 mandible larger, conical, separated by moderate intervals, which are filled 

 with smaller teeth ; teeth also on palatines, pterygoids, and pharyn- 

 geals. Opercular bones very thin. Origin of dorsal and anal fins oppo- 

 site, immediately behind vent, the anal more than twice as long 



