194 Wisconsin Academy of Sciences^ Arts and Letters. 



Pooecetes graiaineus. (Grass finch.) Apr. 14. 

 Food — ^SeejS and insects, 



Molothrus ater. (Cow bird.) Apr. 14. 

 Food ]s chiefly insects. 



Progne subis. (Purple marten.) Apr. 16. 

 Food wholly insectivorous. 



Spizella domestica. (Chipping sparrow.) Apr. 19. 

 Food — Seeds, worms and insects. 



Petrochelidon lunifrons. (Eave swallow.) Apr. 21. 

 Food wholly insectivorous. 



Passerella iliaca. (Fox sparrow.) Apr. 21. 

 Food — Seeds, bugs and insects. 



Pipilo erythrophthalmus. (Chewink.) Apr. 21, 

 Food — Seeds, insects and worms, 



Turdus unalascae nanus. (Hermit thrush.) Apr. 22. 

 Food — Ants, beetles and caterpillars. 



The seed eaters as will be seen by this list, do not appear 

 to arrive in force, until some time after the insect eaters 

 have made their appearance. This is quite contrary to some 

 existing ideas now held by some naturalists respecting these 

 movements. But why these birds are not among the very 

 first, appears to me a singular anomaly. In their case, the 

 temperature must be an important agent in influencing their 

 movements, for their food, the seeds, are as easily obtained 

 in the earlier months, as in May or June, no new plants hav- 

 ing had time to flower before their arrival. 



While the food of a few of the earlier migrants consists 

 chiefly of winged insects, yet the majority of the first comers 

 subsist upon grubs, caterpillars and worms, that are largely 

 found in crevices in the bark of trees, under fallen limbs, on 

 old rails, and in many other similar places. Unless these 

 birds are gifted with the art of discovering larvse and in- 

 sects while in their winter quarters, the awakening of articu- 

 late life must be an important factor in affecting these 

 migrations. 



Mr. F. L. Grundtvig when pursuing his close observations 

 discovered that the yellow rumps (Dendroeca coronata) when 

 they first arrived, associated more or less with the wood- 

 peckers, and like them were successful in obtaining con- 



