206 BULLETIN 101, UNITED STATES NATIONAL MUSEUM. 



Behavior. — While on Bird Rock, where I could easily compare all 

 three species in flight, I learned to recognize the two murres and the 

 razorbills by their shapes and attitudes on the wing. The razor- 

 bill is the shortest and most thick set of the three; it holds itself 

 very compactly, with the head well drawn in and the bill pointing 

 straight forward ; the head, body, and tail are all in a straight line. 

 The common murre on the other hand, carries its long neck and head 

 outstretched, but dropped somewhat below "the level of the body. 

 The Briinnich's murre is intermediate between the two, in this re- 

 spect. All three of these species sway from side to side in flight, 

 showing white breasts and black backs alternately. Their flight is 

 swift and direct, accomplished by very rapid wing strokes. Doctor 

 Townsend (1907) has noted that, as the razorbills "fly away, they 

 show white on either side of a black median line, while the puflm 

 shows a continuous black back." Morris (1903) gives, a quotation 

 from Meyer, regarding their behavior while migrating, as follows: 



During these migrations' an interesting circumstance may be observed, 

 namely, that when the several divisions or groups of a flock descend upon the 

 sea to rest themselves, the parties that are behind alight some distance in 

 advance of those that first settled, so that when the first-arrived parties have 

 recruited their strength and taken wing again, the later-arrived groups having 

 alighted so much in advance, have had time to rest themselves also, and are 

 prepared in their turn to follow in the train of their former leaders as soon 

 as these have passed over. 



The razor-billed auk swims lightly and swiftly on the surface, 

 with its head retracted and its tail pointed upward. It dives quickly 

 and strongly, partially opening its wings as it plunges forward and 

 downward. Like all of the Alcidae, it uses its wings freely in 

 " flying " under water, making great speed with the wings only half 

 extended. Mr. Edmund Selous (1905), who has had excellent op- 

 portunities for studying this, says : 



Razorbills also dive briskly, opening the wings * * *. One remarks then 

 that the wings are moved both together — flapped or beaten — so that the bird 

 really flies through the water. In flight, however, they are spread straight 

 out without a bend in them, whereas here they are all the while flexed at the 

 joint, wing raised from and brought downward again toward the sides in the 

 same position in which they repose against them when closed. 



It can dive to great depths, swim for long distances, and remain 

 under water for a long time. 



The vocal performances of the razor-billed auk are not elaborate. 

 On its breeding grounds it indulges in occasional hoarse guttural 

 notes or low croaking sounds, which are not audible at any consider- 

 able distance. During its courtship, which has apparently never 

 been described, it may have a more varied or interesting vocabulary. 

 Morris (1903) says " the note is likened to the syllables ' arr ' and 

 'odd,' also to 'hurr-ray.'" 



