1!)1:{ I Grinnell-Swarth : Birds and Mammals o] San Jacinto 36] 



represented in the Museum series of this form are: Reehe Canon, 

 near Colton; Garnsey, San Fernando Valley, Los Angeles 

 County; near Wilmington, Los Angeles County. 



Perognathus penicillatus angustirostris < >sgood 

 Colorado Desert Pocket .Mouse 

 This species is represented in the collection by but two speci- 

 mens: no. 1404. from Cabezon, 1700 feet, and no. 1622 from 

 Snow ('reek at 1500 feet altitude. This pocket mouse belongs 

 to the low Lower Sonoran zone of the Colorado desert floor, and 

 its relative scarcity within the San Jacinto region as above 

 indicated probably results from our localities of capture being 

 on the extreme margin of its range. 



Perognathus fallax fallax ('. II. Merriam 



Short-eared Pocket Mouse 



We refer to this race six specimens secured at Vallevista in 

 San -Jacinto Valley (nos. 2272-2277). These were taken in Sep- 

 tember, and five of them are in fresh winter pelage, the sixth 

 being a Juvenal. While this condition of pelage probably ac- 

 counts in part for their distinctly darker tone of coloration, as 

 compared with the large series of the subspecific representative 

 of the species fallax obtained in .May and June on the desert base 

 of the San Jacintos, the relative paleness of the latter as com- 

 pared with the former cannot be altogether due to seasonal causes. 

 The Vallevista specimens are identical with topotypes of fallax 

 from Heche Canon near Colton. Still, as pointed out by Mearns 

 in his description of /'. /'. pallidas (1901, p. 135), the darkest 

 individuals of the species come from still farther towards the 

 coast, so that the Reche Canon and Vallevista representatives 

 may both be considered somewhat intergradienl towards the pah- 

 extreme, pallidas. 



Five adult specimens from Banning (nos. 1465-1469) are 

 distinctly intermediate between fallax and pallidus, and might 

 have been placed with equal propriety under the latter name. 

 This again indicates that the San Jacinto region occupies a pari 

 of the area of intergradation between the coastal race fallax and 

 t he desert form pallidas. 



