OF EASTERN PENNSYLVANIA. 2-1 J) 



is sufficiently borne out by anatomical considerations. In 

 eggs of the same nest-complement, there is noticeable 

 considerable difference in the quantity, intensity, and distri- 

 bution of the pigmentary matter. Eggs that are first extru- 

 ded, being, as a rule, more highly colored, than those which 

 are subsequently laid when the color-supply has been con- 

 siderably consumed. This is most strikingly verified by an 

 examination of the eggs which are successively laid by a 

 female whose nest has been repeatedly robbed ; the last 

 being much lighter and inferior in size than the eggs first 

 laid. The changes are gradual in character, advancing 

 pan' pass it with the exhaustion of the parental reproductive 

 powers. The small egg which is laid by our common 

 Gallus, not much larger than a pigeon's, being the final ef- 

 fort preparatory to ceasing to lay, is only an extreme 

 instance. 



Falco sparverius, Linn. 



This prettv and active little species, which is familiarly 

 known as the Sparrow Hawk, doubtless from the peculiar 

 character of its fare, is somewhat widely distributed 

 throughout the major portion of North America. It was 

 unobserved in the Arctic regions by Macfarlane, and also 

 in Alaska by Dall. The highest points reached are Fort 

 Resolution on Great Slave Lake, and Fort Roe where it 

 is known to breed. On the banks of the Saskatchewan, 

 it is rather abundant according to Sir John Richardson, 

 ft most likely breeds in all parts of North America, from 

 Maine to California, and from Mexico on the south to 

 Hudson's Bay. Although a rare species in the greater 

 part of New England,- it is abundantly found near Calais 

 in Maine; but is a rare visitor in Eastern Massachusetts, 

 while in Williamstown and Amherst, in the west, it has 

 been found to breed. In all parts of the West, Mr. Ridgwav 

 found it very abundant, particularly in the canons of the 

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