572 



during the second and third weeks in July. By the end of August both old and young have 

 entirely forsaken the cliffs, and gone out seaward ; a stiff breeze from the E. or N.E. in this 

 month is said to hasten the autumn migration, and to clear the rocks of their numerous tenants. 



" During the nesting-season the Guillemot flies daily immense distances to and from its 

 feeding-grounds, Flamborough birds going as far south as the Norfolk and Suffolk coasts, and 

 northward to the Durham coast, halfway between the Tees and Tyne, where they are joined by 

 the Farn-Island birds." 



Some interesting notes on the nidification of this bird are also given by Dr. Saxby, who 

 writes (B. of Shetl. Isl. p. 290) as follows: — "Among the crowded ledges it is next to impossible 

 to ascertain whether the Guillemot lays more than one egg in a season ; but by experiments in 

 small retired crevices where there are not more than half a dozen birds, I have satisfied myself 

 that one only is laid, but that if this be removed within a few days another is deposited in its 

 place. Such, however, does not happen when incubation has lasted sufficiently long for the 

 reproductive organs to have nearly regained their normal condition ; but I have never yet tried 

 the effect of removing the second egg. In these outlying situations, also, I have time after time 

 endeavoured to determine the number of days occupied by the process of incubation, but with a 

 not very satisfactory result — calls in other directions, or unfavourable weather, or some equally 

 unavoidable cause, having most provokingly occurred at the critical time. The few trustworthy 

 egg-gatherers whom I have questioned have expressed their belief that exactly four weeks, or 

 twenty-eight days, is the time ; but this estimate seems to be rather under the truth ; at any rate 

 I once discovered a conspicuously marked egg, apparently newly laid, and examined it just thirty 

 days afterwards, and on carefully lifting away a small portion of the shell found a living bird 

 within. With regard to the young birds themselves ornithologists are still unable to decide how 

 it is that, while some remain upon the rocks, others, not many days old, are to be seen swimming 

 in the surrounding waters. 



" Some of the people unhesitatingly assert that they have seen the parents take them upon 

 their backs, and some that they are carried down to the water by the neck ; but none of the 

 men, whose word can be relied upon, would venture to commit themselves to such statements. 

 Macgillivray, who was usually very careful in the collection of his evidence, quotes the words of 

 one of his correspondents, who asserts that the Guillemots ' convey their young to the water by 

 seizing them by the skin of the back of the neck, as a cat does a kitten ;' but he overlooked the fact 

 that his informant wrote from old tradition and had never witnessed the act himself. Mr. Gray, 

 however, in his pleasing account of a visit to Ailsa Craig, states that the keeper, in whose veracity 

 he seems to have confidence, had seen the parents carry them down on their backs, and also by 

 the loose skin of the back of the neck. In the same account the author ingeniously suggests 

 that, where such large numbers of eggs are crowded together, the great diversity of marks and 

 colouring may enable each bird to distinguish its own; but it is necessary to remember that in 

 a short time, especially in rainy weather, the eggs become so spoiled that to recognize any marks 

 of difference requires close scrutiny ; indeed the attempt is sometimes useless. The eggs, how- 

 ever dirty, need much care in the washing, especially when the colouring-matter is new. Those 

 specimens which are purchased, and which, having a very clean appearance, present a patch of 

 ground-colour within a large deeply coloured blotch, have most probably been overwashed, the 



