46 Proceedings of the 



605. Lark Bunting. 683a. Long-tailed Chat. 



607. Western Tanager. 702. Sage Thrasher. 



615. Violet-green Swallow. 703a. Western Mockingbird (S). 



622a. White-rumped Shrike. 715. Rock Wren. 



627a. Western Warbling Vireo. 721a. Western House Wren. 



629b. Plumbeous Vireo. 727c. Rocky Mountain Nuthatch. 



656. Audubon Warbler. ' 7.35a. Long-tailed Chickadee. 



675a. Grinnell Water-thrush (N). 754. Townsend Solitaire. 



680. MacGillivray Warbler. 761a. Western Robin. 



6Sla. Western Yellowthroat. 768. Mountain Bluebird. 



Again, to recapitulate, of the birds that make their home in 

 Nebraska : 



38 find here approximately their center of distribution, 

 31 are more abundant to the northward, 

 6 are more abundant to the southward, 

 94 are eastern birds, and 

 63 are western forms, making a total of 232. 



IV 



The distribution of animal life in Nebraska is such that those 

 who have worked upon the problem have come unanimously to 

 the recognition of five distinct regions, based particularly upon 

 the study of the birds and mammals, but also substantiated by ob- 

 servations made upon other groups. These agree roughly with 

 the phytogeographical areas into which the state has been di- 

 vided,* and correspond to marked differences in topographical 

 and climatological conditions. They have been previously de- 

 finedf as follows : 



1. The Missouri Region, including the wooded bottoms, bluffs, 

 and ravines along the Missouri river, and extending outward 

 along the tributary streams into the next region. 



2. The Prairie Region, including rolling prairies, intersected 

 with streams fringed with a straggling growth of timber, and ex- 

 tending westward approximately half way across the state. Its 



*Pound and Clements. The Phytogcograpliy of Nebraska. Lincoln : 

 1900. 



■''Wolcott. Biological Conditions in Nebraska. Proc. Neb. Acad. Sci., 

 viii : 1906. 



