:>7'2 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



owing to the bad weather, and the men not being able to 

 visit Stack an Arm in and other places, there were not bo 

 many eggs taken as usual. In favourable years it is said 

 that fully 0,000 eggs are taken. These figures, of course, 

 include second layings. It might be thought that this 

 wholesale depletion would clear out the whole Guillemot 

 population, but from my personal observations, and from 

 information supplied me by the natives, I should say that 

 fully one-half of the St. Kildan Guillemots breed undis- 

 turbed : in other words, that there are quite as many 

 inaccessible Guillemot ledges as there are accessible ones. 

 I was able on several occasions to get right in amongsl a 

 crowd of these birds on their nesting ledges, and to pick 

 up the eggs myself. I was, therefore, enabled perfectly 

 to identify some eggs from the Bridled or Ringed form of 

 Guillemot, which was always to be seen on the ledges in 

 company with the common form. I noticed that the 

 Ringed Guillemot was the less bulky bird of the two; 

 thus, two common Guillemots weighed 2Jlbs. each, whilst 

 two birds of the Ringed type weighed respectively 21bs. 

 and 21bs. 2oz. 



These birds are not seen about at all during the winter 

 until about the last week in February, when they begin 

 to make their appearance in the sea, but they are not 

 seen on the rocks until the beginning of March. When 

 they first arrive they come in the early morning, and stay 

 on the rocks till about midday, when they go off to sea 

 and remain at sea until the following morning; they will 

 do that for three days, and then stay away at sea for 

 another three days without coming to the rocks at all : 

 then they will come back again in the early morning 

 for another three days, going off at midday as usual. If 

 the w T eathci is bad they will stay out at sea for six days, 

 instead of three (not, it is said, four or five days), and if 



