1112 REPORT OF STATE GEOLOGIST. 



through close cover, apparently moving earliest in the river valleys. 

 In the Wabash Valley it migrates earlier than elsewhere. The earlier 

 arrivals seek the greater expanses of the valley where there is alike 

 shelter from cold winds and considerable exposure to the sun. There 

 they may be found sometimes from one to two weeks earlier than in 

 nearby neighborhoods. In the extreme southern part of the State 

 they appear in March; in the middle, usually from March 17 to April 

 1, and in the extreme northern portions, usually from April 1 to 15. 

 There is a difference of about a month between the arrivals at Bick- 

 nell, Ind., and Chicago, 111., and Petersburg, Mich. The Brown 

 Thrasher was observed at Hanover, February 25, 1897, by Prof. Glenn 



Head of Brown Thrasher. Natural size. 



Culbertson. This is the earliest it has. been noted in the State. It 

 was reported from Bicknell, March 8, 1894, and March 28, 1895: 

 Spearsville, March 17, 1894, March 31, 1895; Greencastle, March 22. 

 1894, April 3, 1893; Brookville, March 24, 1894, April 18, 1881: 

 Richmond, March 30, 1897; Lafayette, March 25, 1893; Laporte, April 

 1, 1893, April 15, 1894; Dekalb County, April 11, 1896, April 20, 

 1895; Chicago, April 11, 1896, April 28, 1894; Petersburg, Mich.. 

 April 7, 1889, 1893, April 20, 1897. 



The spring of 1894 they migrated very early, while in 1893 they 

 moved late over the southern portion of the State, but pushing north- 

 ward rapidly made early records there. I have observed them mating 

 by March 31 (1884), and sometimes it is kept up until April 23 

 (1889). Years when they arrive at, or after the average time, they 

 seek at once the old quarters occupied by them no one knows how 

 many years. Those arriving after April 1 are usually paired. 



