.SYLVIID.E — THE SYLVIAS. 79 



March, bnt are not known to winter in that latitude. All the .specimens 

 in the Smithsonian collection were obtained between April and October, 

 except one from Southern California, wiiich was taken in December. 



Near Washington, Dr. Cones states the lilue-gray Gnatcatciier to be a 

 sunnuer resident, arriving during tlie first week of April, and remaining 

 until the latter part of September, during which 

 time they are very aljundant. Tiiey are said 

 to breed in liigh open woods, and, on tlieir first 

 arrival, to frecpient tall trees on uhe sides of 

 streams and in orcliards. 



In Californiii and Arizona tliis species occurs, 

 but is, to some ext(;nt, replaced by a smaller 

 species, jiecnliarly western, P. mrliin urn. Tliere 

 they seem to keej) more about low bushes, hunt- 

 ing minute insects in small companies or in 



jiairs, and their habits are hardly distinguish- Poiwpnin cmdm. 



al)le from those of Warblers in most respects. 



The food of this species is chiefly small winged insects and their larva?. 

 It is an expert insect-(!atcher, taking its- prey on the wing with great 

 celerity. All its movements are very rapid; the bird seeming to be con- 

 stantly in motion as if ever in quest of insects, moving from one part of 

 the tree to the otlier, l)ut generally jirelerring the upper branches. 



Nuttall and Audul)on, copying Wilson, sj)eak of the nest of this Gnat- 

 catcher as a very frail receptacle for its eggs, and as hardly strong enough to 

 bear tiie weight of the parent bird. Tliis, however, all my observations 

 attest to be not the fact. The nest is, on the contrary, very elaborately and 

 carefully constructed ; large for tlie size of the bird, remarkably deep, and 

 with thick, warm walls com])osed of soft and downy materials, l)ut abun- 

 dantly strong for its buiUler, wlio is one of our smallest birds l)oth in size 

 and in weight. Like the nests of the Wood I'ewee and the Humming-T^ird, 

 tliey are moi^.els of architec.nral beauty and ingenious design. Witli walls 

 made of a soft felted material, they are deej) antl ])ur.se-like. They are not 

 pensile, but are woven to small upright twigs, usually near the tree-top, and 

 sway witli eath breeze, but the de])th of the cavity and its small diameter 

 ])revent tiie eggs from rolling out. Kxternally the nest is covered with a 

 beautiful periphery of gray licliens, assimilating it to the bark of the decidu- 

 ous trees in which it is constructed. 



Occa-sionally these nests have been found at the height of ten feet from 

 the ground, but they wvv more frequently built at a much greater eleva- 

 tion, even to the heiglit of fifty feet or more. They are made in the shape 

 of a truncated cone, three inches in diameter at the base ami but two at the 

 top, and tliree and a half inches in height. - The diameter of the opening 

 is an inch and a half In Northern (Jeorgia they nest about the middle 

 of May, and are so abundant tiuit the late Dr. Gerliaixlt would often find 



