SCREAMING COW-BIRD 99 



serving the habits of another species (Molothrus 

 badius) I discovered by chance the procreant habits 

 of the Screaming Cow-birds ; and as these obser- 

 vations throw some light on the habits of M. badius 

 I think it best to transcribe my notes here in full, 



A pair of Lenateros (Anumbim acuticaudatus) t or 

 Firewood-Gatherers, have been nearly all the winter 

 building a nest on an acacia tree sixty yards from the 

 house ; it is about 27 inches deep, and 16 or 18 in 

 circumference, and appears now nearly finished. I 

 am sure that this nest will be attacked before long, 

 and I have resolved to watch it closely. 



September 28. To-day I saw a Bay-wing (M. 

 badius) on the nest ; it climbed over it, deliberately 

 inspecting every part with the critical air of a pro- 

 prietor who had ordered its construction, taking up 

 and re-arranging some sticks and throwing others 

 away from the nest. While thus engaged, two 

 Common Cow-birds (M. bonariensis), male and female, 

 came to the tree ; the female dropped on to the 

 nest, and began also to examine it, peering curiously 

 into the entrance and quarrelling with the first bird. 

 After a few minutes she flew away, followed by her 

 glossy consort. The Bay-wing continued 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 behaviour of the two birds 

 struck me very forcibly ; in the great interest they 

 take in the nests of other birds, especially large 



