244 BULLETIN 203, UNITED STATES NATIONAL MUSEUM 



commonly found than four." Dr. Starr says in liis notes that "four 

 eggs are rarely laid, two and three being the usual numbers, while 

 sometimes only one is laid, along with those of the cowbird." This is 

 probably an abnormal situation in which the cowbird fills the nest with 

 its own eggs, leaving little room for those of the warbler. 



The eggs are ovate to short ovate and slightly glossy. The ground 

 color is creamy white and is speckled, spotted, or blotched with "au- 

 burn," "argus brown," "Brussels brown," "chestnut brown," or "cin- 

 namon-brown," with undermarks of "light brownish drab," "vinaceous 

 gray," or "purplish gray." Generally the spots are concentrated at the 

 large end, forming a wreath, but some are marked all over and may 

 also have a few scrawls of blackish brown. I think the handsomest 

 are those having the rich creamy white ground almost immaculate ex- 

 cept for a solid wreath, around the large end, of spots and blotches of 

 the browns overlapping and intermingled with the undertones of gray, 

 so that they resemble somewhat the eggs of the wood pewee. On 

 lightly marked eggs the drab or gray spots are the most prominent. 

 The measurements of 50 eggs average 17.5 by 13.3 millimeters ; the eggs 

 showing the four extremes measure 20.3 by 13.2, 17.9 by 14.8, 14.8 by 

 12.9, and 16.0 by 12.4 millimeters (Harris) . 



Young. — The incubation period for the myrtle warbler is from 12 

 to 13 days and the young remain in the nest normally from 12 to 14 

 days. Incubating the eggs and brooding the young is apparently done 

 entirely by the female, but both parents are active in feeding the 

 young and in cleaning the nest. Mrs. Nice (1930a), with the help 

 of Miss Lucille Baker, watched a nest containing young for a total 

 of 19 hours, over a period of 6 days. On the first day the female 

 brooded 25 percent of the time, but less later on ; the brooding periods 

 averaged 9 minutes. 



A great deal of her energy was expended in delousing the nest — thirty-six 

 minutes on July 28 and seventy-four minutes during the forenoon of the next 

 day, but after that there was little trouble. Once, during thirteen minutes she 

 made over 250 captures, all of which she ate. * * * 



The male brought food sixty times, the female forty-eight times, so that the 

 young were fed once in 10.9 minutes. About one-third of the time the male 

 brought two insects, while the female did so on about one-sixth of her trips. 

 During the fourteen hours of observation, the male brought food once in every 

 nineteen minutes, the female once in every twenty-eight minutes. During the 

 last five and one-half hours, the male brought food once in twenty-two minutes, 

 the female once in eighteen minutes. * * * 



Excreta were eaten by the female through July 29, but she carried one away 

 at 7 : 05 P. M., July 28. She ate twelve sacs and carried eleven ; her mate carried 

 twenty-five and ate one. * * * He picked lice off his legs and gave them 

 to the babies. 



Mr. Knight (1908) says: "The female does most of the work of 

 incubation, but on very rare and exceptional occasions I have found 



