iS8s.] Shufeldt on the Beak of the. Short-tailed Albatross. I^C 



VARIATIONS IN THE FORM OF THE BEAK, 



THAT TAKE PLACE DURING ITS GROWTH, 



IN THE SHORT-TAILED ALBATROSS 



( D 10 MEDEA BRA CHTURA ) . 



BY DR. R. W. SHUFELDT, U. S. ARMY. 



Several years ago when Dr. Bean of the Smithsonian Insti- 

 tution was collecting in various parts of Alaska, he succeeded 

 in securing four heads in the flesh of the Short-tailed Albatross. 

 These were brought back to Washington in alcohol, along with 

 the rest of the excellent material that was gathered during these 

 explorations in our far-off possessions. Last October, before I 

 left Washington for my present field of research in New Mexico, 

 Dr. Bean very kindly presented me with the entire series of the 

 above-mentioned heads, to be used as I saw fit in some of my 

 anatomical studies of the group. 



Before parting with them, however, he invited my attention to 

 the marked differences that existed in the form, as well as the 

 relations of the horny parts that covered the osseous beak. 



The four heads in question undoubtedly belonged to individ- 

 uals of very different ages, ranging from a 'bird of the year' to 

 an apparently full-grown adult. 



The specimen from which the beak in figure i was drawn, 

 has the plumage of the head a yellowish white all over, while 



Figure i. Left lateral view of the beak of Diomedea brachyura, adult. The letters 

 direct attention to the various horny pieces that cover it. From nature, by John L. Ridg- 

 vvay and reduced one-half. 



