284 PROCEEDINGS OF THE 



' fighting for the places on which they were successful in bringing 

 ' out their young formerly. There is every proof that they return 

 ' to the same ledge of rock year after year. I observed one 

 ' female Guillemot browner in colour than hundreds of her 

 ' fellows, who hatched her egg along with other six of the same 

 * species on a small cliff where no person could get to them, but 

 ' where they could easily be seen from a ledge above. This brown 

 ' bird hatched her egg not only on the same rock, but on the 

 ' same place of that rock for three years in succession. At 

 ' another place I saw a Guillemot which had lost a claw. She 

 ' had hatched three years in succession on the same place, and 

 ' when I left in 1870 she was back at the old spot." 



[The regularity in the time of arrival of sea-birds at their 

 breeding stations has been constantly remarked upon by authors, 

 from Martin downwards in chronological sequence, and various 

 references will be found under the different localities in the works 

 treating of them. For the dates of arrival of the various species 

 and of their departure from St. Kilda, see Martin's " St. Kilda," 

 and for the same in more convenient form — and tabulated — see 

 Seton's "St. Kilda," 1879, page 171. The accuracy of Mr. 

 Maclachlan's observations cannot but prove useful to others who 

 may wish to study rock -birds in their haunts, and the time devoted 

 by him to his study of them is sufficient guarantee for their truth- 

 fulness. Few professed naturalists can boast of having lived 

 amongst them for four years. 



Varieties amongst sea-birds are not so frequently met with as 

 among land birds. Still, albinos and other varieties occur not 

 uncommonly. From the Faroe Islands we possess in our collec- 

 tion a fine series of the Puffin — from the typical black-and-white 

 to the albino — speckled, brown-winged, and others, being inter- 

 mediate. The Guillemot and Razorbill also are occasionally 

 obtained of a light brown colour on the back, and also albino and 

 other varieties. Mr. Maclachlan expresses the opinion that the 

 dun varieties are the direct produce of the same stock, or, in other 

 words, that the colour is hereditary; and I think this is fully borne 

 out by our experience of varieties in other species. Mr. Maclachlan 

 thinks that there may be one dun-coloured bird in, perhaps, 400. 



The variety called the Bridled Guillemot is abundant at Barra 

 Head, and in 1870 Captain Feilden and myself were at considerable 

 pains to arrive at an estimate of their numbers in proportion to 



