112 



FIELD COLUMBIAN MUSEUM ZOOLOGY, VOL. V. 



Basin of the Rio Lerma. 



Head 3^; depth 3; D. 17; A. 13; scales 12-29. Body rather 

 robust anteriorly, compressed posteriorly; back little arched; head 

 rather large; interorbital area flattish; its width 2^ in head; mouth 



FlG. 30. ZOOGONETICUS DUGESI (Bean). 

 No. 37831, U. S. National Museum. 



rather large; upper series of teeth large; lower jaw the longer, chin 

 prominent; length of snout 4^ in head; diameter of eye 4; origin of 

 dorsal slightly in advance of origin of anal, midway between tip of 

 caudal fin and posterior margin of eye; pectoral fin T.% in head; 

 ventral 2%; caudal peduncle short, its least depth 2 in head. 



Color light brownish; sides with about 8 dark cross bands, about 

 equal to the interspaces; the bars not always of equal width. Length 

 about 2>2 inches. . 



The young are born about the last week of May. 



Zoogoneticus pachycephalus (Giinther). 



Fundulus pachycephalus Giinther, Cat., vi, 321, 1866; Guatemala: Giinther, 

 Fishes Cent. Amer., 483, pi. 86, fig. 6, 1869; Guatemala. 



A dinia pachycephalus Jordan &Evermann, Bull. 47, U.S. Nat. Mus., 1896, 660. 



Zoogoneticus pachycephalus Meek, Field Col. Mus. Pub., 65, 1902, 94. 



Guatemala. 



Head 3^3 ; depth 3^ to 3*; D. 13 or 14; A. 15; scales 12-35. Body rather 

 deep, head very thick and broad; interorbital space very broad, slightly convex, 

 its width 2 in head; snout broad, obtuse; lower jaw slightly projecting beyond 

 upper; mandible longer than eye; eye 4 in head; origin of dorsal fin slightly 

 in advance of anal, midway between tip of caudal and posterior margin of the 

 orbit; caudal fin subtruncate. 



Color brownish above and on sides, each scale darker on tip; an indistinct 

 dark band along middle of tail ; fins plain, anal fin with the lower margin whitish. 

 (Giinther.) 



Known only from the above description. 



101. Zoogoneticus robustus (Bean). 



Fundulus robustus Bean, Proc. U. S. Nat. Mus., 1892, 285, pi. 

 XLIV, fig. 2; Guanajuato: Jordan & Evermann, Bull. 47, U. S. 

 Nat. Mus., 1896, 644: Jordan & Snyder, Bull. U. S. Fish 

 Comm., 1900, 126; Lago de Chapala: B. A. Bean, Proc. U. S. 

 Nat. Mus., 1898, 541; Lago de Cuitzeo, Michoacan. 



