THE BIRDS OF FAIR ISLE 109 



Down to the year 1910, however, I had not obtained 

 Acanthis linaria in the autumn, though many " Mealy 

 Redpolls" had appeared in the observers' reports as seen 

 between 6th August and 27th December. In the 

 autumn of 1910, however, Acanthis linaria was excep- 

 tionally abundant. The first to appear arrived on i6th 

 October, when several were observed. More followed 

 on the 2 1st, and many hundreds were present at the 

 end of the month, after which they were seen in gradually 

 decreasing numbers down to 28th November — the last 

 date for their appearance in the records. The return of 

 these hosts in the following spring of 191 1 was recorded 

 between 3rd March and 2nd June, the birds being most 

 numerous on 8th May. 



Acanthis holboelli, Holboll's Redpoll. — Among 

 the vast numbers of typical Mealy Redpolls which visited 

 the isle in October 19 10, were several, doubtless many, 

 which belonged to this large form. A few were sent 

 to me as examples of the common bird, the wings of some 

 of which measured 80 mm. I do not regard the birds 

 forming this supposed sub-species ^ as being anything 

 more than large individuals of the ordinary form (^Acanthis 

 linaria). The two completely intergrade as regards the 

 size of their bills and wings — their sole diagnostic 

 characters — arid are found in the same areas in the 

 northern regions of both the Old and New Worlds. 



Acanthis rostrata,^ Greater Redpoll. — This large, 

 dull-coloured, heavily-striped native of Greenland was 

 extremely abundant during our visit in the autumn 

 of 1905. It appeared on 17th September, became 

 numerous by the 25th, still more so on 2nd October, and 

 was common down to the 6th, the day of our departure 



' Acanthis linaria holboelli. ^ Acanthis linaria rostrata. 



