CANADA WARBLER 649 



fibers, fine rootlets, and hair. The outside diameter is about 4 by 

 5 inches, the height about 2i/^, the inside diameter 21/4 by 2^^, and 

 the inside depth 1% inches. 



Eggs. — From 3 to 5 eggs, usually 4, constitute the set for the Canada 

 ■warbler. They are ovate, some tending toward short ovate, and are 

 slightly glossy. The white, or creamy white, ground color is speckled, 

 spotted and sometimes blotched with "chestnut," "bay," or "chestnut- 

 brown," with undertones of "light Quaker drab," or "light purplish 

 gray." On many, the markings are confined to speckles which may 

 be scattered all over the eggs, although they are generally concen- 

 trated at the large end, where frequently they form a distinct wreath. 

 Occasionally eggs may have spots of "Hay's brown" and black, in- 

 stead of the usual red-browns. One set of eggs which I collected is 

 boldly marked with blotches of rich red-browns instead of the usual 

 smaller spots. The measurements of 50 eggs average 17.2 by 13.1 

 millimeters ; the eggs showing the four extremes measure 18.4 by 12.6, 

 18.0 by 14.0, 16.1 by 12.9, and 17.1 by 12.2 millimeters (Harris). 



Young. — The period of incubation for the Canada warbler does not 

 seem to have been determined, nor do we know just how long the 

 young remain in the nest. Data on the development and growth of 

 the young seem to be lacking. The female probably does all, or most, 

 of the incubating and the brooding. Both parents feed the young 

 and remove the excretal sacs. 



Miss Stanwood placed a blind within a few feet of a nest and watched 

 the birds feed the young. Her notes indicate that they are fed at fre- 

 quent intervals, sometimes as often as once a minute, but more often 

 at intervals of from 3 to 6 minutes; occasionally an interval of 15 

 or 20 minutes may elapse between feedings. She saw the male feed 

 several nestlings with a large beakful of yellow grubs that had prob- 

 ably been found in rotten wood. He was seen to catch mosquitoes on 

 the wing and feed them to small young by regurgitation. Green and 

 gray caterpillars and brown measuring worms were fed to the young, 

 and once a large gray moth. If the nest was left long unguarded, 

 it was overrun with insects, but the female usually cleared the nest of 

 such vermin by burrowing under the young and removing them. 



Plumages. — Dr. Dwight (1900) calls the natal down of the Canada 

 warbler sepia-brown, and describes the juvenal plumage, in which the 

 sexes are alike, as "above sepia and, when older and faded, hair- 

 brown. Wings and tail dull olive-brown, faintly edged with dull 

 olive-green; wing coverts paler and indistinctly edged with buff. 

 Below, primose-yellow washed with pale wood-brown on the throat 

 and sides. * * ♦ Practically indistinguishable from S. pusilla 

 except by duller wing edgings." 



