1905.] NATURAL SCIENCES OF PHILADELPHIA. 677 



"During the entire trip more than half of the whole number of days 

 were rainy, and the total precipitation was stated to have been more 

 than often aggregates in this desert region for a period of years. The 

 temperature was correspondingly low, on the 13th reaching 34° with 

 ice in the coffee-pot, something the guide had never seen before in his 

 lifetime of forty-five years. On these accounts the animal life of the 

 region was at a standstill and the results of field work most discourag- 

 ing." 



In the list which follows Mr. Rhoads' field notes are given in quota-" 

 tion marks. 



Ovis canadensis cremnobates Elliot. Lower California Sheep. 



Three females, one of which was adult, obtained in the Cocopah 

 Mountains, near camp, February 24; also a weathered skull and other 

 bones of an old male. 



"Numerous in the Cocopah range. Said to abound on the arid 

 slopes and valleys lying between this and the San Pedro Martir 

 range." 



Sigmodon hispidus eremicus Mearns. Western Desert Cotton Rat. > 



Nineteen specimens of various ages, from the mouth of the Hardy 

 river, the type locality for this race. 



"Abounding in the overflow lands where the tules and reeds were a 

 permanent food supply. Not an upland species, but essentially 

 littoral." 



Reithrodontomys longicaudus pallidus Rhoads. Lower California Harvest Mouse. 



Six specimens from the mouth of the Hardy river. 



"Found only in fine grass on the higher banks — situations, however, 

 which would be temporarily overflowed at highest periods of spring 

 tides and freshets. The Sigmodon was abundant in the same loca- 

 tions." 



Neotoma intermedia albigula (Hartley). White-throated Wood Rat. 



Five specimens from the mouth of the Hardy seem to be referable to 

 this race. 



"The large bush nests of this animal were seen at two or three other 

 points in the delta, including the last camp at Mount Major; here they 

 frequented the rocks also, or possibly this was another species. The 

 habits and homes of this animal on the banks of the Hardy resemble 

 those of the mesquite rats in the vicinity of Corpus Christi, Texas. 

 They subsist largely on the bark and twigs as well as the seeds and pods 

 of the mesquite." 



