A SHORT STUDY OF BIRDS' NESTS. 131 



Of the seventeen which I found and inspected during 

 the summer of 1873, eleven were "bird concealing" in 

 their shape, and the remaining six like the three I found 

 in 1872 i. e., were open at the top. 



During the summer of 1874, Baltimore orioles were 

 unusually abundant, and of the thirteen nests found, 

 eight were open at the top, and five were long, pendulous 

 pouches that wholly hid the sitting bird. 



Bearing in mind the supposed reason for building a 

 nest that would conceal the parent birds when occupying 

 it, I noted down the exact location of each of these thirty- 

 nine nests. In every instance, those that concealed the 

 sitting bird were at a considerable distance from any 

 house, in uncultivated parts, the larger portion being on 

 an unfrequented island ; the others were on elm-trees 

 growing on the banks of a lonely creek. In both these 

 localities sparrow-hawks were seen frequently, when 

 compared with their appearance in the neighborhoods 

 selected for the building of open-topped nests, all of 

 which were in willow and elm trees in the yards of farm- 

 houses, and in full view of people continually passing to 

 and fro. 



The conclusion drawn from the study of these nests 

 was, that the orioles, knowing that there was in this case 

 but little danger from hawks, constructed a less elaborate 

 nest, one which answered every purpose of incubation, 

 though it did not conceal the parent birds when occupy- 



ing it. 



Of the nests that did not conceal the sitting birds, 

 every one was really open at the top, and the bird entered 

 from above. The weight of the bird when in the nest 

 appeared to draw the edges of the rim together sufficiently 

 to shut out all view of the occupant. The rims of those 

 nests that when occupied concealed the birds were all 



