8 BULLETIN 121, UNITED STATES NATIONAL MUSEUM. 



base of the bill and over and under the eyes ; their rumps begin to show a 

 conspicuous spot of white ; the bill turns yellow, with a tinge of carmine, the 

 tip l)luish ; the legs are then flesh color ; and finally the back, wings, and tail 

 become cinereous-brown ; rump, head, and all the under parts pure white ; a 

 white margin shows along the back edge of the wing as the bird flies, and a 

 cloudy black spot generally remains in front of the eye. Thus, in some years, 

 the plumage of the body is changed from nearly black to a pure snow-like white. 



In his Monograph of the Petrels Godman describes in detail the 

 various pkimages of a series of specimens in the British Museum 

 which seem to agree with tlie above statement by Peale. 



Food. — In its feeding habits it does not differ materially from 

 other albatrosses. It occasionally follows vessels for the purpose 

 of picking up what scraps are thrown overboard, though it is shyer 

 than some species and not so constant in its following. It has been 

 caught on a hook and line baited with pork. It evidently feeds 

 largely on squid, and is often attracted by whaling vessels to pick 

 up scraps of blubber and flesh. Where food is so scarce and widely 

 scattered as it is on the ocean, the hungry sea birds can not be too 

 particular about what they eat ; but all the albatrosses seem to prefer 

 animal food. 



Behavior. — The short-tailed albatross bears a superficial resem- 

 blance to the wandering albatross, but it is decidedly smaller and 

 certain details of its color pattern are different. It is said to be 

 less active than some of the other species. In the dark immature 

 plumage it is likely to be confounded with the black-footed albatross, 

 but it is larger and darker, lacks the white face and has a pink bill. 

 Capt. F. W. Hutton's (1903) interesting theory regarding the flight 

 of albatrosses might as well be applied to this species as to any 

 other : 



It was pointed out in 1SS9 by Mr. A. C. Baiues that the birds usually rise 

 in a slanting direction against the wind, turn round in a rather large circle, 

 and make a rapid descent down the wind. They subsequently take a longer 

 or shorter flight in various directions, almost touching the water. After that 

 comes another ascent in the same manner, followed by another series of move- 

 ments. Now, as the velocity of the wind near the surface of the sea is dimin- 

 ished by the friction of the waves, when the bird ascends into the more rapidly 

 moving upper current its vis incrtiae makes the wind blow past it, and so its 

 stock of energy is increased. When it descends it will be moving faster than 

 the lower stratum of wind and will again develop new energy if its inertia 

 is sufllcient to prevent its attaining the new velocity of the wind at once. 

 So that the bird must fly against the wind when ascending and with it when 

 descending. Thus the energy constantly lost by the friction of the air is 

 partially renewed by these maneuvers. This explains why the birds can sail 

 longer in a high wind than in a calm. It is because in a high wind and with 

 a high sea there is much greater difference between the velocities of the wind 

 near the surface and a short distance above it; and this again is an explana- 

 tion of why an albatross keeps so close to the surface of the sea, only just 

 topping the waves and occasionally rising high in the air, 



