BLUE-GR-\Y GNATCATCHER. 



POLIOPTIL.A C.ERULEA. 



Char. Male: above, bluish gray, darker on head, paler on rump ; 

 forehead and line over the eye black ; beneath, pale bluish white ; wings 

 dusky ; tail longer than the body, the outer feathers partly white. Fe- 

 male : similar to the male, but lacking the black on head. Length 4J4 

 to 5 inches. 



I^st. A graceful, cup-shaped structure, saddled on limb of a tree 15 

 or 20 feet from the ground ; composed of felted plant fibre ornamented 

 externally with lichens and lined with feathers. 



Ei^'gs. 3-5; bluish white, speckled with bright brown; 0.55 X 0.45. 



But for the length of the tail, this would rank among the 

 most diminutive of birds. It is a very dexterous, lively insect- 

 hunter, and keeps commonly in the tops of tall trees ; its 

 motions are rapid and incessant, appearing always in quest of 

 its prey, darting from bough to bough with hanging wings and 

 elevated tail, uttering only at times a feeble song of tsee tsee tsee, 

 scarcely louder than the squeak of a mouse. It arrives in the 

 State of Pennsylvania from the South about the middle of April, 

 and seldom passes to the north of the States of New York and 

 Ohio, though others, following the course of the large rivers, pen- 

 etrate into Kentucky, Indiana, and Arkansas. Its first visits 

 are paid to the blooming willows along the borders of water- 

 courses, and besides other small insects it now preys on the 

 troublesome mosquitoes. About the beginning of May it forms 

 its nest, which is usually fixed among twigs, at the height of i o, 

 or sometimes even 50, feet from the ground, near the summit 



