1 I 8 Jones, Bird Migration in lo-va. I ,^ "^j 



my studies of the subject began and continued up to the summer 

 of 1890. With my removal to Ohio in the fall of 1890, and 

 consequent cessation of further study at Grinnell, the purpose 

 to put into permanent and accessible form the results of that 

 work has grown and finally taken definite shape in the present 

 paper. 



No one can realize more than I the insufficiency of the data 

 collected for a final decision upon the points treated. But the 

 conclusions logically reached from a study of these notes may 

 furnish an impetus for further work in the same line. 



From one to eight or even ten hours were spent in the field 

 nearly every day from January until July, and from August 

 until December. An early morning and a late afternoon hour 

 were found to be the most fruitful. Very often this morning 

 and evening work was supplemented by a midday hour, always 

 with note-book and field-glass for ready use, and a gun for 

 emergencies. 



My work was chietiy confined to a region nine miles in 

 diameter near Grinnell, Iowa, latitude 41*^ 44'. The center of 

 this region lay at my home in a small natural grove three miles 

 northwest from Grinnell, on the line between Poweshiek and 

 Jasper counties. 



This grove is of about one hundred acres extent, and is noted 

 in all that region as a place where more species and individuals 

 of birds can be found than anywhere in miles around. It 

 covers five rather high hills which slope to the north and west, 

 and is abruptly terminated on the north by a small stream 

 which flows at the foot of these hills. It is bounded on the 

 south by cultivated fields. The width is about one-half the 

 length, the greater axis running east and west. 



The grove abounds in sheltered nooks and tangled under- 

 growth, but has no swamp nor pool of still water. Oak, hickory, 

 and black-walnut trees are the most numerous, with a fair supply 

 of lindens, poplars, elms, hackberries, wild cherry, cottonwood, 

 locusts and willows. Hawthorn, prickly ash, wild crabapple, 

 wild plum and the black haw abound in thickets; while the 

 hazel bush is the prevailing underbrush. Wild berry bushes 

 are abundant. Wild grape, 'bitter sweet,' and Virginia creeper 



