FISHES OF SINALOA. 479 



Head 3; depth 2; D. XII, 16; A. II, 13; eye 5 in 

 head; snout nearly 2; pectoral 1% ; highest dorsal spine 

 3 in body; ventral 2^ in length; anal lobe 2}^ ; dorsal 

 lobe i^ in body. 



Body compressed and deep; dorsal outline from snout 

 to caudal peduncle uniform; breast prominent and well 

 rounded, behind which the ventral outline is straight to 

 anal spine, then slanting obliquely upward to caudal pe- 

 duncle. Mouth wide with thick lips; the teeth flat, sharp 

 and movable, in a single row in each jaw, those in the 

 upper jaw are arranged in a crescent, in the lower jaw 

 they are in a straight line in front, but at the sides they 

 describe nearly a right angle and run back; isthmus with 

 a notch made by the prominence of the breast. Tip of 

 snout, maxillary and lower jaw naked; head everywhere 

 else with scales, the scales on cheeks in about 5 rows; 

 scales on body large, 3-28-9; all the fins with scales. 

 Accessory scales very few. 



Lateral line running high and ending under last ray of 

 "soft dorsal; gill-rakers numerous, short and weak, about 

 5-I-21. Pectoral short and rounded at the tip; ventrals 

 with the middle rays produced, 2^ times ventral spine, 

 reaching past vent to anal; spinous dorsal low; with 

 the exception of the first the spines are about equal; soft 

 dorsal and anal falcate and filamentous, the dorsal lobe 

 slightly the longer, not quite reaching to tip of caudal fin ; 

 caudal widely forked, the lobes falcate, the upper lobe the 

 longer; the middle rays are contained 3^ times in the 

 upper caudal lobe. 



Specimens described twelve inches in length (Nos. 

 1610, 1636 and 2895, L. S. Jr. Univ. Mus.). 



In life, deep indigo blue, with traces of olivaceous 

 cross -shades. Pectoral, dorsal and caudal edged with 

 bluish white. Eyes violet. 



The species feeds on plants. 



