212 Field Columbian Museum — Zoology, Vol. III. 



Alamo example, two from La Grulla, and two from Hanson Lagoon, 

 which have hoary tails like those of C. v. douglasi, but as the others — 

 some from La Grulla, collected at the same time — have the yel- 

 lowish brown tail similar to that of S. v. beecheyi, it is probably 

 either an individual peculiarity or else one indicating age. What- 

 ever may be the cause, it renders these particular specimens very 

 conspicuous when compared with the others of the series. This 

 spermophile was not uncommon in the localities in which it was 

 found, living among the rocks and following the live-oak zone south. 



FAM. MURID^. 

 ONYCHOMYS. 

 Onychomys macrotis. 



Onychomys macrotis. Elliot. Pub. Field Columb. Mus., 1903, p. 

 155 Zoology. 



4 Specimens: 1 Trinidad, 1 El Alamo, 1 head of San Antonio 

 River, San Pedro Martir Mountains; 1 San Quentin, Pacific coast. 



This genus was apparently very poorly represented throughout 

 the region traversed by Mr. Heller, as the four examples mentioned 

 above were the only ones obtained. It is a pale species with large 

 ears and long tail for an Onychomys, and has nothing in common with 

 O. ramona, its nearest geographical relative from San Bernardino 

 Valley, southern California. I believe the present specimens are 

 the only ones recorded as having been taken in Lower California, 

 although several forms are supposed to inhabit different portions of 

 the peninsula. 



PEROMYSCUS. 

 Peromyscus thurberi. 



Peromyscus thurberi. Allen. Bull. Am. Mus. Nat. Hist., 1895, 

 P- !93- 



Sitomys Americanus medius. Mearns. Proc. U. S. Nat. Mus., 1895, 

 p. 446. 



72 Specimens: 14 Ensenada, 2 El Alamo, 1 Salado River Canon, 

 1 Las Eucinas, 3 Trinidad, 5 head of San Antonio River, 1 San 

 Matias Springs, 2 San Felipe, 2 Aguaje de las Fresas, 6 Vallecitos, 6 

 La Grulla, 3 Santa Rosa, 14 Santa Eulalia, 2 Juncalito, 6 Rosarito, 

 San Pedro Martir Mountains; 4 San Quentin, Pacific coast. 



This species obtained by Mr. Thurber and described by Dr. Allen 

 is but little known to naturalists by specimens from Lower Cali- 

 fornia, as it was supposed to be restricted to the higher ranges of the 



