224 BULLETIN 10 0, UNITED STATES NATIONAL MUSEUM 



middle one of which outside (in front) of lower jaws; lower sec- 

 torial, broad, with oblique triangular cusps. Nostrils oblique, dis- 

 tinct from mouth cavity. Spiracles moderate, with large prespira- 

 cular cavity extending forward to orbit. Body scales pedicellate, 

 crown depressed and smooth above pedicel, edges striate to carinate ; 

 head with sessile and carinate scales. Dorsals small, spines hardly 

 visible or hidden. No anal. Caudal rather short and deep, with 

 subcaudal. Pectorals small, inner angle not extended. 



ANALYSIS OF SPECIES 



a\ Preoral length longer than postocular to first gill opening ; first dorsal smaller 

 than second dorsal which inserted over midventral base owstonii 



o^ Pectoral length equals postocular to first gill opening; dorsals equal, second 

 inserted opposite hind end of ventral base fuscus 



CENTROSCYMNUS OWSTONII Garman 



Centroscymnus owstonii Gabman, Bull. Mus. Comp. Zool., vol. 46, p. 207, 1906 

 (type locality: Yenoura, Suruga Gulf, Sagami Bay). — PiErrscHMANN, Sitz. 

 Ber. Akad. Wiss. Wien, math.-nat. Kl., vol. 117, pt. 1, p. 671, text fig. 

 4, 1908 (head below) (Japan). — Garman, Mem. Mus. Comp. Zool., vol. 36, 

 p. 205, pi. 13, figs. 5^8, 1913 (type).— Fowler, Proc. 4th (1929) Pacific Sci. 

 Congr., Java, p. 495, 1930 (reference). 



Centroscymnus owstoni Regan, Ann. Mag. Nat. Hist., ser. 8, vol. 2, p. 49, 1908 

 (reference). 



Depth 6% to subcaudal origin; head 4l^, width 1%. Snout 3 in 

 head; orbit 3^^, 1% in snout, 1% in interorbital ; mouth width 2% 

 in head, moderately curved, deep groove at each angle; labial folds 

 short, upper longer, hidden by groove; teeth in 72 row^ above, 36 

 below, narrow upper lanceolate in 3 groups separated by smaller 

 teeth, median group widest and most prominent and functions out- 

 side (in front) of lower jaws, lateral groups narrower and function 

 inside (between) lower jaws; lower teeth wide, compressed, single 

 series functional except when about to be shed, cusps obliquely 

 directed outward; nostrils oblique, small, first % in snout, valve 

 broad, internarial 214 in preoral length, which 2% in head; inter- 

 orbital 2%, low. Gill openings small, % of orbit, before pectoral. 

 Spiracle medium, backward and above from eye, externally sep- 

 arated from orbit by twice their width. 



Scales pedicellate, on flanks and back comparatively smooth and 

 rounded above pedicel; over head, shoulder, and belly with 3 to 5 

 weak keels. 



First dorsal origin about opposite depressed pectoral tip, height 

 half length of free portion which long as base, fin length 1% in head ; 

 second dorsal origin over middle of ventral base, fin length 1% in 

 head, height equals 1% height of first dorsal; dorsal spines weak, 

 very little exerted ; caudal 3% in rest of body, front subcaudal edge 



