THE FAUNA OF BOULDER COUNTY, 

 COLORADO^ 



By T. D. a. Cockerell 



Boulder County has an area of only 751 square miles, but within 

 its borders are four or five different life-zones, the altitudes ranging 

 from a httle over 5,000 to 14,271 ft. The mean annual rainfall is 

 said to be about 17 inches, and the mean annual temperature 45° 

 to 50° Fahr., but these figures lose much of their significance in view 

 of the very different conditions obtaining in different parts. 



A catalogue of the flowering plants and vascular cryptogams of 

 the county, by Dr. Francis Daniels, will shortly be published by the 

 University of Missouri. This list is fairly complete, but the enumera- 

 tion of the fauna is much more difficult. The vertebrates have 

 been recorded about as well as the higher plants, but the inverte- 

 brate fauna is still very incompletely known and undoubtedly includes 

 multitudes of species not yet collected and identified, a fair propor- 

 tion altogether new to science. The synopsis which follows must 

 therefore be regarded only as a beginning, and it is hoped that in 

 course of time it will be replaced by another, representing a much 

 more advanced stage of knowledge. This desirable advance will 

 be possible only through the co-operation of many workers, the 

 field being much too large to be covered by any individual. 



Several groups not mentioned in the present contribution have 

 been reviewed in previous numbers of these studies, as follows: 

 Birds, Vol. VI, No. 3; Fishes, Vol. V, No. 3; MoUusca, Vol. IV, Nos. 

 2 and 3; Crustacea, Vol. V, No. 4; Bees, Vol. IV, No. 4, and VII, 

 No. 3 ; Scale Insects, Vol. II, No. 3 ; Ants, Vol. VII, No. 4. 



» Publication of the Colorado Biological Survey, No. i. The Biological Survey of Colorado was 

 organized recently by the Regents of the State University, with Professors Ramaley, Cociierell and Hender- 

 son in charge. It is intended to continue and amplify the work (long in progress without definite organiza- 

 tion) on the fauna and flora of Colorado, living and extinct. While the work has been organized at the State 

 University, we hope to secure the co-operation of naturalists in various parts of the state and of specialists in 

 other states. 



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