OF EASTERN PENNSYLVANIA. 157 



The eggs are a beautiful crystalline-white, and 

 are dotted and blotched around the larger ex- 

 tremity with purple, reddish-brown, and dark 

 umber. They measure about .64 of an inch in 

 length, and .53 in breadth. The size varies with 

 the latitude; the largest coming from Kansas, and 

 the smallest from Georgia. Within its nest, we 

 have frequently found the eggs of Molpthrus 

 pecoris, as many as two at a time. 



Geothlypis Philadelphia, Baird. 

 The Mourning Warbler is one of the rarest of 



o 



our spring migrants. It makes its appearance 

 early in May, and retires north to breed not later 

 than the 22cl of this month. We have observed 

 it but once in four years. It is a solitary bird, and 

 delights in low bushes, rather than high, open 

 thickets which most Warblers are accustomed to 

 frequent. 



It is fearless and unsuspecting, and suffers itself 

 to be approached without exhibiting the least 

 alarm. In habits, it resembles the species last 

 described in many particulars. In search of in- 

 sects, it is an energetic creature, clambering alonof 



o o o 



the branches of small shrubs, and freely suspend- 

 ing itself from their extremities,* head downward; 

 and as often darting forward with notable skill to 



o 



secure some passing insect, which it accomplishes 

 with nearly the dexterity of a Flycatcher. When 

 molested, it does not seek safety in prolonged 

 flight, or climb to the tops of tall trees, but merely 



