LIFE HISTOBIES OF NOETH AMBKICAN DIVING BIBOS. 143 



and thus fall well within the limits of the measurements of the eggs 

 of both hypolemms and craven. 



There is an egg in the collection of Mr. Charles E. Doe which is 

 said to be of this species and it looks as if it might be correctly, 

 identified. It was taken by Mr. A. H. Dunham, of Nome, Alaska, 

 on June 10, 1904. The egg was found on rocky land above the Iron 

 Eiver about 70 miles north of Nome; the parent birds were also 

 taken. In general appearance it much resembles the egg taken by 

 Mr. Cantwell. In shape it is " elliptical ovate." The color is " mas- 

 sicot yellow " and it is uniformly, but not thickly, covered with small 

 spots of " bone brown " and " deep quaker drab." It measures 60.5 

 by 37.5 millimeters. 



Plumages. — ^Even less is known about the downy young; for, so 

 far as I know, no specimen has ever been taken. In the Juvenal 

 plumage the young bird is pure, clear, "blackish brown" above, 

 except for the white on the scapulars, and the under parts are finely 

 barred with dusky. The dusky barring on the under parts disap- 

 pears during the fall and winter; usually by the end of November 

 the under parts are pure white, as in the adult, but sometimes traces 

 of the barring remain until February. Young birds can hardly be 

 distinguished from adults during the first winter, but they have 

 blacker backs, without so much plumbeous. This first winter plum- 

 age is worn without much change throughout the first spring or until 

 the first postnuptial molt, when young birds become indistinguish- 

 able from adults in the winter plumag^. 



Adults have two conspicuous seasonal molts producing strikingly 

 different plumages. The prenuptial molt, which includes every- 

 thing but the wings and tail, sometimes begins early in February, 

 but more often not until March or April; it is often well along in 

 May before the beautiful, marbled plumage of the spring adult is 

 completed. The postnuptial molt is complete. It occurs mainly in 

 September and October, but it is often prolonged into November; 

 during this molt the heavier, dark, crescentic markings on the under 

 parts, which are the last of the spring plumage to disappear, will 

 serve to distinguish adults from young birds. By the latter part of 

 November, at the latest, adults are in their full winter plumage and 

 can be distinguished from young birds by having pure white imder 

 parts and more plumbeous on the upper parts. 



Food. — The food of the marbled murrelet seems to consist largely 

 of fish which it obtains by diving in the tide rips and other places 

 where it can find small fry swimming in schools. Doctor Grinnell 

 (1910) writes: 



At the head of Cordova Bay a dozen or so were observed; one shot, dis- 

 gorged fishes 3 Inches In length. 



