32 NESTS AND EGGS OF BIRDS. 



quarters, sought to expel the rightful owners. The flycatchers 

 resisted, and the property-owner shot the female bluebird, tiaink- 

 ing to put an end to the disturbance. The male instantly flew 

 away, but returned in half an hour with two females and 

 renewed the contest, gaining the victory. The flycatchers, 

 however, did not retire until they had thrown out the nesting 

 materials, a portion of which they afterward carried away to 

 use elsewhere. After the defeat the bluebird selected a part- 

 ner from his allies, and the discarded female retired. The pro- 

 prietor, perceiving a strong predilection upon the part of the 

 bluebirds for the can, determined to annoy them awhile, fas- 

 tened a lath across the entrance and watched the result. The 

 bii'ds went to work, and by their persevering efforts the piece 

 was soon dislodged. After that the brood was raised in peace 

 and were fed almost exclusively upon the larvae of two species 

 of turnip or cabbage butterfly {Pieris)^ and the wingless bodies 

 of Spilosoma., a moth destructive to the grape. 



Into her chosen tenement the female conveys enough of a 

 peculiar kind of grass, which turns dark red when it dries, some- 

 times mixing with it a little hair, to carpet thickly the bottom 

 of the cavity. This is all the furniture, and she seems to attend 

 to all the details of its preparation, while the male sings and 

 caresses her. In the northern states this bed is finished and 

 the first eggs are deposited by the middle of April ; in the south 

 much earlier. Mr. Gentry discusses the question Mjhy the blue- 

 birds seek cavities as nesting places ; and concludes that it is 

 because such situations best secure the requisite warmth and 

 safety for their young. He thinks it probable that in primi- 

 tive times hollow trees were occupied more generally than at 

 present by all birds, just as now they ai'e constantly used as 

 hospices by our winter denizens during inclement weather. 

 The argument is that the bluebird leai'ned to build in cavi- 

 ties by first using such places for shelter dui'ing cold spring 

 storms ; and, perceiving their comfort and convenience, came to 

 regard them as appropriate quarters for nesting. Thus what 

 was to their ancestors merely accidental, has now become in- 

 tuitive and habitual to the race. Protection is also thus afforded 

 against rapacious birds which would quickly catch sight of the 

 bright plumage of the female in an exposed nest. 



