WILD LIFE OF ORCHARD AND FIELD 



however, that of the nests that did conceal the sit- 

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

 the bird entered from above. Its weight, when in 

 the nest, appeared to draw the edges of the rim to- 

 gether sufficiently to shut out all view of the occu- 

 pant. It is his opinion, however, that years ago, 

 when its enemies were more numerous, the nest of 

 this oriole was perfectly closed at the top, and with 

 a side opening; but he finds none so now. 



The question why this species alone among our 

 birds is supposed to have learned by dear experi- 

 ence to take such precautions against its foes has 

 already been answered : it is because the Baltimore 

 oriole is almost the only species in which the fe- 

 male is not protected from observation by her neu- 

 tral and dull colors. 



Nuttall thought both sexes equally expert at 

 nest-building, although the labor principally de- 

 volved upon the female; the latter clause in par- 

 ticular others have confirmed, and the rule is that 

 the male occupies himself only in collecting materi- 

 als for his mate. They labor very steadily, but a 

 week's work is necessary for the completion of their 

 home. It seems strange that domiciles construct- 

 ed with so much pains should not be occupied suc- 

 cessive seasons, but this seems never to be the case. 



259 



