ORCHARD ORIOLE 199 



colored and more neutral tints are nearly always present to a greater or less extent. 

 The average measurement of one hundred and thirty-three specimens in the 

 United States National Museum collection is 20.47 by 14.54 millimetres, or 

 about 0.81 by 0.57 inch. The largest egg in the series measures 22.35 by 15.24 

 millimetres, or 0.88 by 0.60 inch; the smallest, 18.03 by 14.22 millimetres, or 

 0.71 by 0.56 inch. 



Young. — Bendire (1895) says: "Incubation lasts about 12 days, 

 and I am of the opinion that this duty is exclusively performed by 

 the female. I have never seen the male on the nest, but have seen 

 him feed his mate while incubating. I believe as a rule only one 

 brood is raised in a season. Both parents show equal solicitude and 

 devotion in the care and defense of their young from prowling enemies, 

 and will boldly and furiously attack any intruder." 



Grimes (1931) doubts if the period of incubation exceeds 12 days, 

 says that only one brood is raised each year, and that "male and 

 female share the task of incubating the eggs, and both feed and brood 

 the young, which leave the nest when ten or twelve days old. Food 

 for the young, which I have noticed consists largely of katydids, is 

 usually secured at a distance of one hundred yards or more from the 

 nest. * * * The female is by far the more solicitous of the pair 

 when the eggs or young are in danger." 



In the seven nests under daily observation, Dennis found the pe- 

 riod of incubation, from the first egg laid to the first hatched, to be 

 12 days in one nest, 15 days in one, and 14 days in the other five. 

 The young were fledged in from 11 to 14 days. 



In her observations on a family of orchard orioles in Wisconsin, 

 Winnifred Smith (1947) noted that "the female did all the incubating. 

 * * * During three hours the male fed the young 23 times, the 

 female 14 times. Feces were carried off or eaten by the male eight 

 times and only once by the female." After the young had left the 

 nest, the "male undertook the care of two fledglings while the female 

 took care of one. The male chased the female when she attempted 

 to feed the two in his charge. * * * The family remained in the 

 vicinity until July 30 after which they were not seen again in 1946." 



Plumages. — D wight (1900) describes the juvenal plumage of the 

 orchard oriole as "above, including sides of head and neck, pale gray- 

 ish olive-green, buffy on rump. Below, pale sulphur-yellow. Wings 

 pale clove-brown, the primaries and secondaries narrowly edged with 

 dull white, the median and greater wing coverts with pale buff form- 

 ing two indistinct wing bands. Tail yellowish olive green." 



The first winter plumage is acquired by a partial postjuvenal molt, 

 beginning late in July, at which time only the wing-quills and the 

 tail feathers are retained. In this plumage both sexes are much like 

 the adult female in winter. A limited prenuptial molt, mainly about 



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