Jordan and Evermann. — Fishes of North America. 2449 



2807. CERDALE lONTHAS, Jordan & Gilbert. 



Head 7f iu length; depth lOf. D. 41; A. 36 to 38; C. 4-17-4; P. 12; V, 

 2. Body considerably elongate, compressed, of nearly equal depth 

 throughout, the head tapering rapidly from occiput to snout; snout short, 

 not obtuse, but the lower jaw heavy and blunt, much projecting beyond 

 the preniaxillaries; gape very short and oblique, the tip of the premaxil- 

 lary not reaching ventral from orbit. Margin of upper jaw formed en- 

 tirely by the premaxillaries, which are free laterally, but scarcely mov- 

 able uiesially. Maxillary not distinguishable, probably enveloped in the 

 integument of the snout. Teeth rather strong, short, blunt, in a double 

 series in each jaw, apparently wanting on the vomer and palatines. Lips 

 developed laterally, where they form a fold around the angle of the mouth; 

 lower lip adnate mesially, the upper reduced to an obsolete fold. Length 

 of gape ); length of head. Nostrils 2, distant, the anterior at the end of 

 the snout, almost labial, the posterior above front of orbit, both circular. 

 Eye very small, somewhat less than interorbital width or than length of 

 snout. Distance from snout to past margin of orbit contained 2f times in 

 length of head. Pseudobranchi;e well developed. Gill openings very nar- 

 row, reduced to a short, nearly horizontal slit, extending forward from a 

 point just below the lower base of the pectoral fin. Branchiostegals evi- 

 dent, apparently 4 in number. Vertical fins well developed; dorsal and 

 anal both long, the membrane of the last ray of each joining the base of 

 the rudimentary rays of the caudal. Distance from occiput to the origin 

 of dorsal fin equal to the length of the head; rays of dorsal fin very slen- 

 der, distinct, the membrane thin and transparent, the rays all, or nearly all, 

 articulate, the anterior simple, the posterior bifid at tip. Vent slightly in 

 advance of middle of length of body, the anal fin beginning immediately 

 behind it; anal rays bifid at tip, excepting the first 2, which appear sim- 

 ple; tail not isocercal, truncate at base of caudal, most of the rays of the 

 caudal springing from the expanding last vertebra; caudal fin rounded, 

 1 length of head, its rays much branched, more closely set than the rays 

 of the dorsal and anal; rudimentary rays very numerous; ventral fins 

 small, close together, inserted slightly in advance of the lower end of the 

 pectoral, each fin composed of 2 rays, the inner prolonged beyond the 

 outer, and bifid at tip, about as long as pectoral fin and * length of head; 

 pectorals well developed, broad, the rays branched at tip. Head and body 

 entirely covered with small scales, which are close set but hardly imbri- 

 cate, not arranged in series; mandible, snout, and gill membrane scaly; 

 scales on belly and breast smaller than the others and more thickly set; 

 base of caudal and pectoral fins scaled. Coloration in life, body translu- 

 cent light olive, immaculate below ; back and sides very finely marked 

 with clusters of fine dots, the ground color appearing as reticulations be- 

 tween the clusters, which are of irregular size and form; on the sides of 

 the head these dots form bars, which radiate from the eye to the snout and 

 lower side of the head. This species is known from 3 specimens, 2\ to 3 

 inches in length, taken in a rock pool at Panama, {iovddc,, freckled.) 



Oerdale ionthas, Jordan & GrLBERT,BuU. U. S. Fish Comm. 1881, 332, Panama. (Coll. Chas. 

 H. Gilbert.) 



