PREFACE. 
The present catalogue, although based essentially upon the 
list published in 1874, in the Annals of the Lyceum of Natural 
History of New York (vol. x. pp. 364-94) is rendered much 
more complete by the addition of nearly thirty species, and 
many facts which have been brought to light by subsequent 
investigations. The most important sources from which this 
additional information has been derived are the several lists of 
Illinois birds published by my friend Mr. E. W. Nelson, 1 of 
Chicago (now II. S. Signal Observer at St. Michaels, Alaska), 
but I have also been furnished with many interesting facts 
through correspondence with persons actively engaged in the 
study of the ornithology of the state, among whom I may 
especially mention Dr. J. W. Yelie, of the Chicago Academy of 
Sciences, Mr. H. K. Coale, of Chicago, and Mr. C. K. Worthen, 
of Warsaw; the information thus derived being duly acknowl- 
edged in the proper places. 
To the 311 species of the catalogue of 1874, there are here 
added 31, which would bring the total number known to occur 
in Illinois up to 342 were it not for the fact that one species 
( Podiceps cristatus ) was included upon erroneous information, 
and is therefore eliminated. Of the 341 species enumerated 
herein, no less than 213 are positively ascertained to breed 
within the limits of the state. Not a single species has been 
included except upon good authority, while, on the other hand, 
several are excluded on account of not having been actually cap- 
tured within the state, though some of them have been secured 
near Racine, Wisconsin, in the extreme southeastern corner 
of Wisconsin, rendering it therefore extremely probable that 
individuals of the species in question have at one time or another 
iFor the titles of these, see pp. 168-170. 
