28 BULLETIN L30, UNITED STATES NATIONAL MUSEUM 



white patch. The progi-ess toward maturity is very slow, and even in 

 May the young male has only partially assumed the adult plumage ; 

 the tail and much of the body plumage has been renewed, the wings 

 are still immature, and the head has acquired large white patches, 

 but only a few of the purple feathers of the adult. A complete 

 summer molt occurs in July and August, after which the adult 

 plumage is gradually assumed and is completed in November and De- 

 cember. The young male thus becomes adult at an age of 17 or 18 

 months. The young female makes practically the same progress to- 

 ward maturity. 



I have never seen the eclipse plumage of the bufflehead, but accord- 

 ing to Mr. Millais (1913) both old and young males assume " a fairly 

 complete eclipse, resembling a similar stage of plumage in the 

 goldeneye." 



Food. — The bufflehead obtains its food by diving, usually feeding 

 in small companies so that one or more remain on the surface to 

 watch for approaching dangers while the others are below; some- 

 times only one remains above, but it is only rarely that all go below 

 at once; should the sentinel become alarmed it communicates in 

 some way with the others which come to the surface and all swim 

 or fly away to a safe distance. 



Neltje Blanchan (1898) describes its feeding habits very neatly, 

 as follows: 



A bufflehead overtakes and eats little fish under water or equally nimble 

 insects on the surface, probes the muddy bottom of the lake for small shell- 

 fish, nibbles the seawrack and other vegetable grow^th of the salt-water inlets, 

 all the while toughening its flesh by constant exercise and making it rank by 

 a fishy diet, until none but the hungriest of spoilsmen care to bag it. 



Audubon (1840) says: 



Their food is much varied according to situation. On the seacoast. or in 

 estuaries, they dive after shrimps, small fry, and bivalve shells ; and in 

 fresh water they feed on small crayfish, leeches, and snails, and even grasses. 



Ora W. Knight (1908) says that in the inland regions of Maine 

 " they feed on chubs, shiners, small trout fry, and other small fish. 

 Along the coast their diet is very similar." Other writers include 

 in their food various small mollusks, crustaceans, beetles, locusts, 

 grasshoppers, and other insects. 



Dr. F. Henry Yorke (1899) lists the following genera of plants 

 among the food of the bufflehead: Limnohium.. Mynophyllinn, 

 Oallitriche, Utricularia., and Pontederia. Vegetable matter seems 

 to form only a small part of the food of this species and is eaten 

 mainly during the summer. 



Behavior. — The flight of the bufflehead is exceedingly swift and 

 direct, generally at no very great elevation above the water, and is 

 performed with steady and very rapid beats of its strong little 



