142 BULLETIN 121, UNITED STATES NATIONAL MUSEUM. 



nest during the day and fed at night on the semidigested oily food 

 which its parent regurgitates. Mr. Norton (1881) says of it: 



This little creature is ^Yortlly of more than a passing notice. The observer 

 is instantly impressed with the fact that this mass of down shields a living 

 form. It does not sprawl like the helpless young of the passeres, but is nearly 

 as helpless ; by an effort it can stand, and raise its head to gaze at objects, but 

 locomotion is beyond its feeble strength except in a very limited degree. It 

 lays at full length with its feet placed by its side and the tip of the bill resting 

 on the ground, usually asleep or in restful inactivity, while its rapid breathing 

 testifies that it is not dead. If aroused, it raises its head with an air expressive 

 of wonder, very often giving vent to its voice in a few low queaks. All of its 

 movements are accomplished with the impulsiveness of childhood. It is pleas- 

 ingly fearless, gazing at its captor, or making feeble efforts to secure a com- 

 fortable position in the hand, and when this is accomplished, pleased with the 

 warmth, it will settle down for a nap. 



FluTnages. — The young bird is rather slow in developing and re- 

 mains in the nest a long time, often well into September, or until it is 

 fully fledged and ready to fly. When first hatelied it is covered with 

 long, soft, thick down var3dng from " hair brown " at the base to 

 " smoke gray " at the tips. It becomes very fat and often exceeds 

 the adult in bulk. The plumage appears first on the wings, tail and 

 back, and then on the breast ; the last of the down finally disappears 

 on the lower bell3^ Doctor Grinnell (1897) says: 



The feathers grow from the same follicles as the down, and in continuation 

 with the latter. As the juvenile grows larger, the down wears off from the ends 

 of the feathers and thus gradually disappears so that finally hardly a trace is 

 left. This wearing away of the down is first noticeable on the wings, back, 

 and breast, and is due to the bird's movements in the narrow nest-cavity. 



The first plumage assumed is practically the same as that of the 

 adult and subsequent molts do not show any well-marked seasonal 

 diiferences. The annual molt of adults probably takes place in 

 August and September. 



Food. — The Leach petrel skims the surface of the ocean to pick up 

 its floating food. It is particularly fond of animal oils or oily food 

 and will follow in the track of a wounded seal or whale to feed on the 

 traces of oil which have flowed from its wounds. It also follows 

 living whales to pick up the bits of food which the feeding whale 

 has left floating on the surface. It may also be seen flitting over the 

 sea in wide circles in the wake of a ship to pick up what chance 

 morsels of greasy food may have been thrown overboard. Fishermen 

 cleaning fish at sea are soon surrounded by petrels which appear as 

 if by magic as soon as the offal is thrown upon the waters; they are 

 especially fond of the oily cod livers and can be easily tolled up 

 to the boat by scattering such dainty morsels on the surface. When 

 feeding thus they seldom settle on the water, as the albatrosses and 

 shearwaters do, but hover close to the surface, rising over the waves, 



