MAY, 1902. THE ICHTHYOLOGY OF MEXICO MEEK. 93 



contained 38 well developed young, each .75 inch in length. 

 The young taken from a single fish are very uniform in size. 

 These specimens were collected May 19 to 21. The specimens 

 taken from Lake Chapala, May 31 to June 2, had all spawned 

 out. Spawning time for this species is second and third weeks 

 in May. 



Alimentary canal scarcely as long as the body; peritoneum 

 grayish: origin of dorsal fin midway between base of caudal and 

 anterior margin of opercle. The young of this species much 

 resembles the young of Goodea atripinnis, the small spots being 

 smaller and more pale. A good sized Gambusia infans was taken 

 from the stomach of one of the fishes taken in Ocotlan. Ocotlan; 

 Patzcuaro; Zirahuen. 



Zoogoneticus diazi, sp. nov. 



Type, No. 3618, F. C. M. Length, 2.60 inches. 



Locality, Lago de Patzcuaro, Patzcuaro, Michoacan, Mexico. 



Head 3$; depth 3$; D. 17: A. 14; scales 34-13. Body 

 elongate, robust, more compressed than in Z. robustus ; back 

 much elevated, forming a prominent angle at the nape: top 

 of head slightly convex; interorbital width 2^ in head; snout 

 bluntish; mouth large, lower jaw the longer; chin very prominent; 

 snout 4 in head; eye moderate, its diameter 3^ in the head. Dor- 

 sal fin slightly in advance of the anal, its origin midway between 

 base of caudal and posterior margin of opercle. 



Base of dorsal i| in the head, its height 2 (in male I-3-) in 

 head: anterior dorsal ray short, the anterior rays gradually increas- 

 ing in length to the eighth or ninth, which is the longest. Pec- 

 toral fin 1 1 in the head; ventral 2-|. 



Alimentary canal scarcely as long as the body; peritoneum 

 light; teeth in a band in each jaw, all of them conical, the 

 outer series being the larger. 



Light olivaceous, much mottled with darker, which forms 

 irregular cross bars on the sides; many of the larger specimens in 

 life with a reddish tinge over the body, which fades to nearly a 

 uniform light olive; fins all plain. The males are a little duller 

 and of a more uniform color than are the females. Largest 

 specimen, a female 3.60 inches in length. The few males ob- 

 tained average smaller than the females. 



This species is close to Z. robustus. It differs from that spe- 

 cies in having larger scales, a less advanced and longer dorsal 

 fin. The coloration is also much different and the flesh less firm. 



