OF EASTERN PENNSYLVANIA. 35 



sequences, providently managing with a constant 

 aim for future comfort, convenience and necessity. 

 Let us now recur to other facts of nidification. 

 The nest being completed, which is ordinarily the 

 case in five days, a short time intervenes prior to 

 oviposition. But a single ovum is deposited daily. 

 After the full complement of eggs is laid, the 

 female immediately assumes the duties of incuba- 

 tion, which happen in the beginning of June, and 

 continue for a period ranging from 1 2 to 1 3 days. 

 The male bird seldom departs any considerable 

 distance from his partner, except to provide 

 himself and her with food; but we have never 

 known him. to relieve her during • incubation. 

 Should any being approach the nest, he assails 

 the intruder with commendable boldness. Various 

 species of serpents, particularly the black-snake, 

 "the Bascanion constrictor of naturalists, have a de- 

 cided penchant for the eggs of the Cat Bird. On 

 occasions of visits from these snakes, the birds 

 heedless of their own safety, frequently fly into the 

 very jaws of their enemy. In the case of a human 

 foe, knowing that resistance would be futile, they 

 seek to deter him from any supposed attack- by the 

 most discordant cries and frantic gestures. 



The young are not very fastidious. Earthworms, 

 spiders, diptera, caterpillars of non-irritating prop- 

 erties, together with such berries as the season 

 affords, constitute their fare, 'in about 12 days 

 after being hatched, the young leave the nest, and 

 in 6 days more are ready to be initiated into the 



