MAY, 1902. THE ICHTHYOLOGY OF MEXICO MEEK. 97 



ing markings of quarter grown specimens; length of young .55 

 inch. A second female 2.50 inches in length, from the same 

 place, contained 23 young, each .46 inch in length. 



A female 2.70 inches in length, taken at Aguas Calientes, June 

 7. contained 37 young, each .40 inch in length. 



Some of the females from Huingo collected May 26, are gravid. 

 Aguas Calientes; Lagos; Celaya: Ocotlan: Huingo. 



CHAPALICHTHYS, gen. nov. 



Type. Characodon encaustus Jordan & Snyder. 



Body rather deep, compressed; caudal peduncle long and slender. 

 About three-fourths of the dorsal fin in front of the anal; origin of 

 dorsal midway between base of caudal and anterior margin of orbit; 

 anal fin of male with first 5 or 6 rays shorter and separated from the 

 other rays by a shallow notch; teeth in two series; the outer enlarged, 

 bicuspid and firmly attached; the inner series small, and in small 

 patches. 



Alimentary canal elongate, convolute, or irregularly in three 

 coils on the right side, its length nearly twice the total length of the 

 fish: peritoneum black; caudal fin truncate. 



This genus has the long alimentary canal of Goodea and the firm 

 bicuspid teeth of Characodon. The dorsal fin is considerably more 

 advanced in this genus than in either Goodea or Characodon. 



Gill-rakers long and slender, 24; vertebra? 184-19 = 37. 



Chapalichthys encaustus (Jordan & Snyder). 



The dorsal fin of the male is higher than that of the female; 

 longest dorsal ray of male ifa in head, of female i^ in head. 

 Anal fin of male with its first rays short arud stiff. 



Longest female 3.50 inches; longest male 2.70 inches. The 

 number of females greater in our collections than are the males. 



Viviparous; one female 2.70 inches in length, contained 

 21 young; size of young very uniform, each .40 inch in length. 

 Egg not entirely absorbed. La Barca; Ocotlan; La Palma. 



Cyprinodon elegans Girard. 



A comparison of a large series of specimens from Northern 

 Mexico shows considerable variation in color and fin markings. 

 Males from Chihuahua have a very pale dorsal: those from 

 Minaca. Jimenez and Santa Rosalia have the dorsal light, with 

 some cluskv on the base or on last rays. Males from Guzman 



