106 



unsexed, kept alive, in transitional plumage). The first bird (in 

 breeding plumage) which nearly had finished moulting (a moderate 

 number of growing downfeathers on head and neck) was received 

 on April 28th, 1922; twenty others however, all from the last 

 week of April, were all moulting rather strongly. Many birds begin 

 much later and only show the first traces of moult at the end ot 

 March or the beginning of April (cf March 29th, 1921, with the 

 first growing downfeathers); about the middle of April transition 

 becomes somewhat more general but even at the end of April a 

 number of birds still seems to be in complete winterdress, though 

 the inside of their skin of course shows a number of growing feathers 

 (4 out of 8 received on April 24th 1922). I only could examine a few 

 May-birds but we may accept for sure, that transition is general 

 till the middle of May and that the moulting period has not yet 

 come to an end at the end of May ^). So it lasts in these birds 

 (which are in their first spring) from the second half ot 

 February till the end of May or later. 



Alca torcla L. — About 130 specimens were examined, 120 ot 

 which were received from December 1st onward 

 to May. 



Bird older than two years. — Three to four furrows^) 

 in the bill. 



The moult of the so called old Razorbill begins considerably later 

 than that of the old Guillemot. Not any one of the December- or 

 January- birds showed growing feathers, the first specimen in moult 

 was received in the second half of February (9, February 21st, 1922, 

 winterplumage, strong moult on the inside of the skin of head 

 and neck, where the colour will be changed). In the first half ot 

 March most birds are moulting fully and some of them already are 

 in nearly complete or even complete breedingdress (9, March 10th, 



1) Le Roi (1911) found in birds, collected in the isle of Lungsk (Lofoten) 

 and Spitsbergen, on 7 June 1908 and 17 June 1907 respectively, „am Unter- 

 hals noch eine Anzahl Winterfederchen". I don't believe that these feathers 

 still had to be moulted for the last traces of moult of the head and the 

 neck are nearly always to be found on the chin and not on the underpart 

 of the neck. 



2) Though it is no real furrow^, I consider the white stripe on the bill as 

 the first furrow and the first real furrow as the second furrow. 



