194 
years and averaged as a group 624 to the square mile, while the num- 
bers of the 114 remaining species amounted to 228 to the mile. 
THE most ABUNDANT Birps By SECTIONS OF THE STATE 
Eighty-five species and one variety of birds were recognized and 
counted in southern Illinois in the summers of 1907 and 1909 and 
twenty-two of these were so abundant as to comprise 83 per cent. of 
the total number of birds, leaving but 17 per cent. for the other sixty- 
four species. Otherwise stated, twenty-two species averaged 250 birds 
each while the remaining 64 species averaged only eighteen each. The 
more common 25 per cent. of the different kinds of birds were about 
fourteen times as numerous per species as the less common 75 per cent. 
The commoner group of 22 species averaged 638 birds to the square mile, 
and the less common group 130 to the mile, the former with one bird to 
the acre and the latter with about five acres to the bird. 
NUMBERS OF PRINCIPAL SUMMER BIRDS 
OF SOUTHERN ILLINOIS IN 1907 AND 1909 
(22 SPECIES) 
(83 PER CENT. OF ALL THE BIRDS SEEN) 
Meadowlark: 7s. a..tccm cite tee ce ie aero ears 1293 
TONES TISH AS PALLO Weyretersic peicds areroreeateta steve crete 795 
MOuTHIN | WOVE Xie aa sons ee ee Oe 518 
Hield ASPATTOW) Sistas c's cccte acie a cisiecstotere isin te 322 
IDiekcissel!y sii... .c-xsel-tavemiarviclciate ase '<rsieke aheterers 314 
Red-winged blackbird................. 278 
Bronzed Veracklet ich cis..(cevw cietectete cl beitenios 274 
Quail. Sole k steseteras cre cee e lalate eats ne EE 241 
RODIN iie?stotiesis woes, “ees tae Perea teres 165 
Brown ethTashericcw sic aateitaomete 137 
KANE DIN mugen peisterstocan ofemaval stearate 119 
GOW DING sh rctcrarantaxel eycte ate cinencncie eens oekeeee 116 
Mocking bird! i cys sie iciexcissctaretarentiaetelielaneeteas 112 
BlWes Jay”. es clatororets nie aden etete sueboale satiate 111 
Red-headed woodpecker ............... 105 
Orchard oriolesc:s: o5..,7Osecss oo eens 103 
Bivepirdis ate eer hs dlavelagersvalhjalerapecats mheherens 96 
Grasshopper Sparrow ........sc-cseres 93 
KU de er. 2 ii Fesiee otctecete esc aisieveternete earns 87 
BIT CKO TS crests are eciene svepeveitsy ots eine eee eae 82 
Maryland yellow-throat ............... 78 
Indigo sDuUNEIN gece me ale wisi a eet are eke 75 
Total st. Pi cicisietels ese tuetciattre crepenetaperetoets 5514 
When we come, however, to compare southern with central Illinois, 
we find a striking difference in respect to the number of dominant ~ 
species. The southern part of the state is much more broken and diversi- 
fied than the central—contains, that is, a greater variety of situations, 
each with its more or less definite group of characteristic or dominant 
