CATBIRD 329 



of the nest. Later another of the robin's eggs was found on the ground 

 with a punctured side as if a large needle had pierced it. 



Plwmage. — In the juvenal plumage of the catbird the pileum is a 

 dull sooty brown, many shades lighter than that of the adult. The 

 wings and tail are nearly black as in the adult, the primaries and 

 secondaries edged with smoke gray, the coverts browner edged, the 

 tail with indistinct barring ; the interscapular region brownish ashy, 

 shading into pale mouse gray indistinctly mottled with clove brown 

 or rufous, the throat and sides faintly tinged with sepia, the crissum 

 pale, dead cinnamon or mars brown. Bill and feet dusky pinkish 

 buff becoming black. 



The first winter plumage, according to Jonathan D wight (1900) — 



is acquired by a partial postjuvenal moult, beginning early in August, which 

 involves the body plumage and the wing coverts, but not the rest of the 

 wings nor the tail, young and old become practically indistinguishable. Simi- 

 lar to the previous plumage but much grayer and no mottling. Everywhere 

 clear slate-gray, much paler below and on the sides of the head and neck ; 

 the pileum black ; the crissum deep chestnut. 



The first nuptial plumage acquired by wear which produces little obvious 

 change. 



The adult winter plumage acquired by a complete post-juvenal moult in 

 August. Practically indistinguishable from the first winter; the wings and 

 tail perhaps averaging blacker and with grayer edgings. The adult nuptial 

 plumage acquired by wear as in the young bird. 



According to Chapman (1916) "some females have the crown and 

 upperparts slightly browner than in the male but they vary too 

 little to make the sexes certainly distinguishable. The catbird shows 

 no geographic variation throughout its wide range." 



Some individuals present a variation in the relative amount of the 

 chestnut coloring of the crissum. Lincoln (1920) reports that a 

 specimen captured at "Washington, D. C, had an extreme restriction 

 of the chestnut. "Basally," he says, "there was no trace of chestnut 

 which was present only in the form of a very narrow edging (in no 

 place as much as a sixteenth of an inch in width) beginning about 

 midway of the feathers and continuing around the tips." 



Alexander Wetmore (1936) has determined the number and 

 weight of the contour feathers of many of our passeriform birds. 

 In a catbird obtained June 4, 1933, weighing 35.6 grams, there were 

 1,733 contour feathers weighing 2.3 grams. 



Albinism is of relatively common occurrence in the catbird; many 

 both pure and partial albinistic forms have been reported of which 

 the following are representative. Mrs. F. L. Battell (1941) writes 

 of seeing two albino catbirds that appeared with the parent cat- 

 birds at Ames, Iowa, during the summer of 1940. Although nearly 

 full grown they were still fed by the adults. Tlie young were pure 

 white, even the feathers of the crissum being without a trace of 



