150 FIELD COLUMBIAN MUSEUM ZOOLOGY, VOL. V. 



aa. Anal rays 6 to 8. PAGE 



b. Side with a black band made up of more or 

 less distinct spots about as large as eye ; dorsal 



rays 9; anal rays 6; scales 9-28 latipunctata 150 



bb. Side without black band. 

 c. Origin of dorsal nearer tip of caudal than tip 

 of snout ; dorsal rays 7 to 9 ; anal rays 6 to 8 ; 

 scales 9-24 to 28. 



d. Head large, 3^ to 3^ in body; depth 2^ 



to 3 % butleri 151 



dd. Head small, 4^ in body ; depth 3 1 / to 4^ presidionis 152 



cc. Origin of dorsal nearer tip of snout than tip 

 of caudal. 



e. Least depth of caudal peduncle 6 in length 

 of the body ; head 4 ; depth 3^ ; dorsal rays 



8 or 9 ; anal rays 6 or 7 couchiana 152 



ee. Least depth of caudal peduncle 5 in the 

 length of the body; head 3^; depth $y z ; 

 dorsal rays 9 ; anal rays 8 sphenops. 153 



140. Poecilia occidentalis (Baird& Girard). 



Heterandria occidentalis Baird & Girard, Proc Acad. Nat. Sci. 

 Phila., 1853, 390; Rio Santa Cruz, Tucson, Arizona: Jordan & 

 Evermann, Bull. 47, U. S. Nat. Mus., 1896, 689. 

 Girardinus occidentalis Girard, Mex. Bd. Sur., 73, pi. xxxix, fig. 

 16-19, 1859; Rio Santa Cruz: Girard, Proc. Acad. Nat. Sci. 

 Phila., 1859, 119; Rio Santa Cruz, Tucson, Arizona. 

 Girardinus sonorensis Girard, Proc. Acad. Nat. Sci. Phila., 1859, 



120; San Bernardino Creek, tributary of the Rio Yaqui. 

 Poecilia occidentalis Garman, Mem. Mus. Comp. Zool., 1894, 61; 

 San Bernardino Creek, Arizona: Rutter, Proc. Cal. Acad. Sci., 

 1896, 261; Opsura (Rio Yaqui); Hermosillo: Rutter, ibid., 267; 

 Rio Santiago, Tepic. 



Rivers of Sonora and southern Arizona. 



Head 3>; depth 3^ to 4; D. 7 or 8; A. 9 or 10; scales 8-29. Body 

 deep, elevated in front of dorsal; origin of dorsal nearer base of caudal 

 than tip of the snout, slightly in advance (?) of anal. 



Color brownish above, dotted with black ; silvery below ; with a black 

 lateral stripe as broad as eye from shoulder to caudal ; a narrow black 

 line along lower margin of tail; fins plain, without spot or blotch. 



141. Poecilia latipunctata sp. nov. 



Type, No. 4484, F. C. M., 2% inches in length; Forlon, Tamaulipas 

 Basin of the Rio Panuco. (Forlon.) 



