40 MY STUDIO NEIGHBORS 



are among its most frequent dupes, given some- 

 what in the order of the bird's apparent choice: 

 song -sparrow, field - sparrow, yellow warbler, chip- 

 ping - sparrow, other sparrows, Maryland yellow- 

 throat, yellow - breasted chat, vireos, worm -eating 

 warbler, indigo-bird, least-flycatcher, bluebird, Aca- 

 dian flycatcher, Canada flycatcher, oven-bird, king- 

 bird, cat -bird, phcebe, Wilson's thrush, chewink, 

 and wood-thrush. 



But one egg is usually deposited in a single 

 nest; the presence of two eggs probably indicates, 

 as in the case of the European cuckoo, the visits 

 of two cow-birds rather than a second visit from 

 the same individual — the presence of two cow- 

 bird chicks of equal size being rather a proof of 

 this than otherwise, in that kind Nature would 

 seem to have accommodated the bird with an ex- 

 ceptional physiological resource, which matures 

 its eggs at intervals of three or more days, as 

 against the daily oviposition of its dupes, thus giv- 

 ing it plenty of time to make its search and take 

 its pick among the bird-homes. Whether the 

 process of evolution has similarly equipped our 

 cow-bird I am not aware ; but the vicious habits 

 of the two birds are so identical that the same 

 accommodating functional conditions might rea- 

 sonably be expected. It is, indeed, an interesting 



