BIRD NOTES IN 8 ARK. 309 



authenticate. One boatman says you can always tell, because the egg 

 of the Lesser Black-back is darker in colour, i. e. the background is 

 browner in this bird and greener in the Herring-Gull, and that in the 

 former the blotchings assume a deeper intensity of colour as to be 

 almost black in some cases, whereas in the Herring- Gull the markings 

 never get to a much deeper shade than deep umber-brown. I am in- 

 clined to think he was not altogether wrong either, for some eggs I 

 knew to be Lesser Black-backs were much darker than the Herring- 

 Gull's, and two — one of each species — taken from the same nest, are 

 quite dissimilar, one being dark, and the other — the Herring-Gull's — 

 lighter. But some of the eggs obtained were intermediate in colour- 

 ing between dark and light, and might equally well belong to either 

 species. 



Great Black-backed Gull (L. marinus). — Saw two of these noble 

 birds on an isolated rock off the Courbee du Nez, at the northern end 

 of the island. I am not able to say whether or not they breed here- 

 abouts. 



Stormy Petrel (Procellaria pelagica). — When on the Petite Moie, I 

 most distinctly detected the musky odour that is always present near 

 this bird's breeding haunt, and I have little doubt that a nesting bird 

 was within a few feet hidden away in some secret crevice in the rocks. 

 Our boatmen, too, noticed it, and, curiously enough, had never seen or 

 heard of such a bird before ; nor did their knowledge come forward 

 when I referred to the Storm Petrel as " Mother Carey's Chicken." 

 But since this pelagic little wanderer only comes to land for a few 

 weeks to incubate its solitary disproportionate egg, and is very 

 nocturnal in habits and small in size, it is perhaps no wonder that 

 these fishermen have never noticed it. 



Razorbill (Alca torda). — This bird and the next named are both 

 called indiscriminately by the fishermen " Divers." They say they 

 often take the Razorbill and the Guillemot on their lines when fishing 

 at some considerable depth. In Sark the Razorbill breeds on Les 

 Autelets, but apparently not nearly in such large numbers as the 

 Guillemot. 



Common Guillemot (Uria troile). — Their chief, and, I believe, 

 only breeding station is on Les Autelets, and here a considerable 

 number were at all times of the day to be observed sitting on the 

 ledges, no doubt incubating their eggs. Les Autelets are practically 

 inaccessible, though they have been scaled by some foolhardy climbers 

 bo it was impossible to get near the breeding ledges, but round the base 

 of the rocks several broken eggs were found. 



