THE PUFFIN. Ib 3 



this it appears that the adult Puffin in spring has the beak elevated at the base, 

 the lower mandible regularly curved from the base to the extremity. The beak 

 is divided into two parts ; one, the anterior portion remains unaffected by the 

 moult ; the other, the posterior undergoes the following changes. It is formed 

 by the combination and suture of nine horny pieces which disunite and fall apart 

 after the breeding season. The beak is then smaller, and much less deep at the 

 base ; the lower mandible forms, instead of a regular curve, a rounded obtuse 

 angle the apex of which is at the division between the anterior and posterior 

 portions of the beak. The posterior portion of the bill has lost some of its 

 thickness. At the same time the thick puckered skin, forming a large rosette of 

 an orange-yellow at the gape is reduced to a narrow band ; while the wide thick 

 border of orange-red round the eye has lost its colour, and the two horny flakes 

 of bluish-grey, one above triangular and the other beneath elongated (horizontally) 

 are wanting. In conclusion Mr. Harting writes that Dr. Bureau observes that : 

 " The adult bird .... owes its summer dress to phenomena of three kinds 

 hypertrophy, formation of horn, and colouration ; and loses it under the influence 

 of three inverse phenomena, namely, atrophy, loss of horny substance, and loss 

 of colour." 



Dr. Sharpe states that the black shade on the face is present in all the 

 specimens killed in winter, so far as the British Museum collection is concerned, 

 even when the bill is developed to its full size. He adds : " Whether this is a 

 sign of immaturity, or whether it is also a mark of winter plumage in the adults, 

 I am unable to say for certain" ("Handbook to the Birds of Great Britain"). 



In the young bird the bill is not so deep ; the culmen is only slightly curved 

 and does not rise abruptly, where it joins the forehead, for a short distance as in 

 the adult in winter ; there is only one slight ridge on the upper mandible ; the 

 angle of the gonys is shallow, much shallower than in the adult in winter, and 

 the gonys between the angle and the tip of the bill forms a nearly straight line. 

 The face and sides of the head and chin are dusky grey, and there is a patch of 

 dull black in front of and partly round the eye. The collar is sooty-grey and 

 hardly complete in front. " In some cases the dark face is still retained when the 

 bird begins to breed in its third year" (H. Saunders). 



The young in down is uniform blackish-brown (Seebohm). 



The Rev. M. A. Mathew saw a Puffin at Skomer Island which had pure 

 white wings. Selby mentions the occurrence of white varieties, and there is one 

 in Mr. Marshall's collection. Others have been obtained at St. Kilda. 



