8 ANNALS OF SCOTTISH NATURAL HISTORY 



in not a few instances their occurrence admits of no reason- 

 able explanation, though this cannot be said to be the case 

 with our Fair Isle captures. The rarities alluded to were the 

 Arctic Redpoll (Acanthis hornemanni\ a species not hitherto 

 detected in Scotland, of which several specimens were 

 obtained ; the Yellow -browed Warbler (Phylloscopns super- 

 ciliosus), the second Scottish example ; the Bluethroat 

 (Cyanccula suecica}, not previously known to have occurred 

 in either the Orkneys or Shetlands ; the Lapland Bunting 

 {Calcarius lapponicus), a rare visitor to Britain, but present 

 in numbers at Fair Isle ; and the Green Sandpiper (Totamis 

 ocJiropus], another species not previously detected as visiting 

 our Northern Islands. A rare visitant was seen, but not 

 obtained, namely, a Little Bunting {Emberiza pusillci}, of 

 which only one occurrence has previously been recorded for 

 Scotland. 



At such a favourably situated and compact station it was 

 possible to have one's finger, as it were, on the pulse of the 

 feathered stream rushing southwards at the season of our 

 visit ; to note its fluctuations, either as quickening under 

 influences highly favourable, or its slackening or arrest during 

 stressful periods, or, again, its even flow under normal con- 

 ditions. Here, too, we could note the sequence of arrivals 

 and departures, and be able to ascertain what was new each 

 day and what had passed on ; also the duration of the 

 movements of a number of species. 



An opportunity was also afforded for the correlation 

 of the migratory movements observed with the varying in- 

 fluences of the weather conditions. To this end the Weather 

 Reports for Europe issued by the Meteorological Office have 

 been consulted, and a comparison instituted between the two 

 sets of phenomena. 



Owing to the total absence of cover, except the brackens 

 alluded to, the patches of potatoes and turnips formed our 

 main hunting grounds for migrants among the passerines ; but 

 while these afforded most effective shelter for the travellers, they 

 proved to be most difficult ground for the work of observers. 

 The immigrants were loth to quit these hiding and resting 

 places, and usually only did so on being close pressed, when 

 they took a very short rapid flight and dived, as it were, into 



