BLACK-THROATED GREEN WARBLER. 71 



searching for food, regardless as it were of the presence of man. Its 

 movements when proceeding northward are rapid, and it advances 

 through the woods solitarily or nearly so, it being seldom that more 

 than two or three are foimd together at this time, or indeed dm'ing the 

 breeding season, at which period each pair appropriates to itself a cer- 

 tain extent of ground. Its retrogade march is also rapid, and by the 

 middle of October they all seem to have passed beyond the limits of 

 our most southern States. 



The food of this species consists during the summer months of va- 

 rious kinds of flies and caterpillars, many of the former of which it 

 captures by darting after them from its perch, in the manner of Fly- 

 catchers and Vireos, emitting like them also a clicking sound from its 

 bill. In the autumn it is often seen feeding on small berries of vari- 

 ous sorts, in which respect also it resembles the birds just mentioned. 

 I never found the nest of this bird, of which, however, Mr Nuttall 

 has given a minute description, which I shall here, with his permission, 

 place before you. " Last summer (1830), on the 8th of June, I was 

 so fortunate as to find a nest of this species in a perfectly solitary situa- 

 tion, on the Blue Hills of Milton. The female was now sitting, and 

 about to hatch. The nest was in a low, thick, and stimted Virginia 

 juniper. When I approached near to the nest, the female stood mo- 

 tionless on its edge, and peeped down in such a manner that I imagined 

 her to be a young bird ; she then darted directly to the earth and ran, 

 but when, deceived, I sought her on the ground, she had very expertly 

 disappeared ; and I now found the nest to contain four roundish eggs, 

 white, inclining to flesh-colour, variegated, more particularly at the 

 great end, with pale purplish points of various sizes, interspersed with 

 other large spots of brown and blackish. The nest was formed of cir- 

 cularly entwined fine stripes of the inner bark of the juniper, and the 

 tough white fibrous bark of some other plant, then bedded with soft 

 feathers of the Robin, and lined with a few horse hairs, and some slen- 

 der tops of bent grass (Agrostis ).'''' 



My friend describes the notes of this species as follows : — " This 

 simple, rather drawling, and somewhat plaintive song, uttered at short 

 intervals, resembles the syllables ''te de' territica, sometimes tederisca, 

 pronounced pretty loud and slow, and the tones proceeding from high 

 to low." These notes I am well acquainted with, but none can de- 

 scribe the songs of our different species like Nuttall 



