401 
Bs ie Sixty-nine per cent. of the birds belong to 34 permanent resident 
oe ae. and 31% to 7 species of winter residents, the latter mainly 
_ juncos, purple finches, tree sparrows, and white- throated sparrows. ‘ 
“Central and northern Illinois resembled each other and differed from we 
a Illinois in the fact that although they are widely unlike in the g 
= tatistical particulars of our survey, the winter fields of both were swept 
vy ranging flocks of virtually the same gregarious species, which made by 
_ far the greater part of the bird population of both sections. Six species 
out of thirty recorded composed, in these northern sections, 8% and 88 
“x cent. of the whole number seen. The two following lists of species 
of principal winter birds differ only in the substitution of the junco in 
_ central Illinois for the Lapland longspur in northern ; and their combina- 
tion into one improves our picture of the winter bird life of these parts 
& of the state. 
NUMBERS OF THE PRINCIPAL WINTER Birps or CENTRAL 
Inurnots, 1906 AND 1907, (88.5 PER CENT. LIST) 
- - Numbers Numbers per 
_- . _ Species | seen square mile 
i _ Crow 526 128 
os Prairie horned lark 338 82 
be = English sparrow ~ 332 81 
‘Sea ; — Goldfinch 153 37 
= : Junco ; 141 34 
— ; Tree sparrow 113 27 
yess aaa, ot ae = 
; Total ~ 1603 389 
? 1g@ te 
; * NUMBERS OF THE PRINCIPAL WINTER Birps or NorrTHEeRN 
“" ILLINOIS, 1906 AND 1907, (87 PER CENT. LIST) 
q : Numbers Numbers per 
3 ~ Species seen square mile 
. Lapland longspur 675 186 
= Crow 207 57 
Goldfinch 179 49 
oa! Tree sparrow 137 38 
5 Prairie horned lark 75 21 
English sparrow 50 14 
Total | - "1328 365 
