THE COWBIRDS. 617 



first bird. After a few niiiintes she flew away, followed by her glossy 

 escort. The Bay-wiiig contiuued its strange, futile work until the 

 owners of the nest appeared, whereupon it hopped aside in its usual 

 slow leisurely manner, sang for a few moments, then flew away. The 

 similarity in the behavior of the two birds struck me very forcibly. In 

 the great interest they take in the nests of other birds, especially in 

 large covered nests, the two species are identical. But when the 

 breeding season comes their habits begin to diverge; then the common 

 Cowbird lays in nests of other species, abandoning its eggs to their 

 care, while the Bay-wings usually seize on the nests of other birds and 

 rear their own young. Yet, as they do occasionally build a neat, elab- 

 orate nest for themselves, the habit of taking possession of the nests 

 of other birds is, most likely, a recently acquired one, and probably its 

 tendency is to eradicate the original building instinct. 



October 8. — This morning, while reading under a tree, my attention 

 was aroused by a shrill note as of a bird in distress issuing from the 

 neighborhood of the Lenatero's nest; after hearing it repeated at 

 intervals for over twenty minutes I went to ascertain the cause. Two 

 Bay- wings flew up from the ground under the nest, and on searching in 

 the rank clover growing under the tree I discovered the female Lefiatero, 

 with plumage wet and draggled, trembling and appearing half dead 

 with the rough treatment she had experienced. I put her in the sun, 

 and after half an hour, hearing her mate calling, she managed to 

 flutter feebly away to join him. The persecutors had dragged her out 

 of the nest and would, no doubt, have killed her, had I not come so 

 opportunely to the rescue. 



Since writing the above, I have continued to watch the nest. Both 

 the Bay-wings and Leilateros left it for some days. Six days after 

 picking up the ill-treated female, the Lenateros came back and resumed 

 possession. Four days later the Bay-wings also came back; but on 

 finding the nest still occupied, they took possession of an unfinished 

 oven of an Ovenbird on another tree within L'O yards of the first, and 

 immediately began carrying in materials with which to line it. When 

 they had finished laying I took their 5 eggs, at the same time throwing 

 down the oven, and waited to see what their next move would be. 

 They remained on the spot singing incessantly, and still manifesting 

 anxiety when approached. I observed them four days, and then was 

 absent from home as many more; on returning I found that the 

 Lenateros bad once more disappeared and that the nest was now held 

 by the Bay- wings. I also noticed that they had opened an entrance 

 very low down at the side of the nest which they were using; no 

 doubt they had killed and thrown out the young Lenateros. 



It was now early in November, the height of the breeding season, 

 and numbers of common Cowbirds constantly visited the nest; but I was 

 particularly interested in a pair of Screaming Cowbirds that had also 

 begun to grow fond of it, and I resolved to watch them closely. As 



