PACIFIC FRESH WATER FISHES. 267 



L. S. Jr. Univ. Mus.), the largest 1% inches long, from 

 a branch of the Rio Grande de Santiago at Tepic, 

 Mexico. 



The species is named for Dr. Gustav Eisen, who col- 

 lected it with the following species in 1894: 



Poecilia occidentalis (Baird & Girard). 



Numerous specimens of this species were taken with 

 the above. They do not differ from specimens from 

 Hermosillo. 



