309 



the ratios of abundance and the birds per square mile of the eighteen 

 species of this amended list. The seventy-four native species remain- 

 ing are now represented by 499 birds — an average of 1 to about 

 seven acres; a proportion far too small to have any general signifi- 

 cance. 



Tabi,e II. The Eighteen Most Important Native Birds, 

 Indiana Line to Quincy. 



Species 



Crow-blackbird 



Meadow-lark 



Crow 



Co wbird 



Horned Lark 



Mourning-dove 



Swamp-sparrow 



Goldfinch 



Myrtle warbler 



White-throated sparrow 



Field-sparrow 



Vesper-sparrow 



Quail 



Flicker •• 



Robin 



Bluebird 



Killdeer 



Blue jay 



The Vegetable Covering of the Soie. 



As the area traversed on this trip was almost wholly under culti- 

 vation, the relation of these birds to the vegetable covering of the soil 

 was virtually their relation to the agricultural and horticultural crops 

 of central Illinois in autumn — almost entirely to the former, since 

 the horticultural area is comparatively insignificant in this part of the 

 state. Nearly all this surface was in fields of ripe corn, the stalks 

 standing in some fields and in others cut and shocked ; in blue-grass 

 pastures ; in meadows of timothy, clover, and millet, or timothy and 

 clover mixed ; in fields of stubble, mostly after a crop of oats ; in fields 

 of young wheat ; in ground freshly plowed, mainly as a preparation 

 for wheat ; and in orchards, almost all of apple. Plowing for wheat 

 was in progress when the trip began, and fields of young wheat were 

 reported in increasing numbers after October 1. Some of the later 

 plowing was doubtless done for corn. 



