Genus Cullospcrmophilus 



The ground-squirrels of tliis genus have side stripes, rather 

 prominent ears, body robust, tail short and skull broad. 



Colorado Species. 



Say's Ground-Squirrel, Callospermophilus lateralis lateralis. 



Wortman's Ground-Squirrel, Callospermophilus wortmani. 



These gTOund-squirrels are commonly known as the big chip- 

 munk, and range over the western part of the State at an eleva- 

 tion of about 6,000 feet to about 10,000 feet. Tlie food of these 

 ground-squirrels is seeds of various kinds and garden truck. In 

 some localities they are a great pest to mountain gardeners. 



Genus Ammospermophilus 



The ground-squirrels of this genus are of small size with 

 small ears and short tail. They are inhabitants of tlie sandy 

 arroyos covered with sagebrush and greasewood, and are also 

 found to some extent among the rocks, around the edges of these 

 arroyos. 



Only one species of the Antelope-squirrels occurs in the State, 

 and that is Ammospermophilus hucurus cinnamomeus. It occurs 

 in southwestern Colorado. I have observed it at Palisade and 

 Hotchkiss, and Warren also reports it from Montrose, Coventry, 

 Bedrock and western Montezuma County. 



We know nothing of the food habits of this antelope-squirrel, 

 but it can hardly be of any economic importance. 



Genus Sciurus 



The tree-squirrels belong to this genus. The eastern gray- 

 and fox-squirrels are well-known members, and are familiar to 

 most of the residents of the State, because of early association in 

 the East and Middle West. The gray- and fox-squirrels are not 

 natives of Colorado, but have been introduced into several parks 

 in different sections. However, the genus is well represented in 

 the mountainous portions of the State, where the pine-squirrel or 

 chickaree, and the tuft-eared-squirrels occur. The members of this 

 genus all have long, bushy tails. 



Colorado Species of Tree-Squirrels. 



Mimic-Squirrel, Sciurus aherti mimus. 

 Plainbacked-Squirrel, Sciurus aherti ferreus. 

 Pine-Squirrel, Sciurus fremonti fremonti. 



27 



