THE FRIGATE -PETREL. 421 



strikes the water with its feet when flying low to pick up food. 

 Ogilvie- Grant states " Short grunting note when caught on 

 eggs, much like that of domestic Pigeon under similar circum- 

 stances." (P. R. Lowe.) 



Breeding-habits. — Breeds in burrows in sandy soil in large 

 colonies. Apparently no nest made, single egg being laid on bare 

 soil. Egg. — White, without gloss, and usually well-defined zone or 

 cap of fine red spots at large end, with violet shell-spots. Average 

 of 22 eggs, 36.2 x 26.5. Max. : 37.3x26.7 and 36.9x27.4. In.: 

 33.8x25.7 and 37x25.4. Breeding -season. — About April 27 on 

 Great Salvage Island, but eggs and young in mid-March on Cape 

 Verde group. Incubation. — By both sexes. Period unknown. 



Food. — No definite information. 



Distribution. — Great Britain. — Two. One picked up dead Walney 

 Island (Lanes.), Nov., 1890 (H. A. Macpherson, Ibis, 1891, p. 602). 

 Young female caught alive Colonsay (I. Hebrides) Jan. 1, 1897 

 (W. E. Clarke, Ann. S.N. H., 1897, p. 88). 



Distribution. — Abroad. — Nests on Salvages and Cape Verde 

 Islands and has been obtained on Azores (once), Canaries, and 

 Madeira, also on coast of Massachusetts (U.S.A.). Allied subspecies 

 (P. m. marina) inhabits Tristan d'Acunha, Nightingale Is., and 

 probably other islands in southern Atlantic, and is found in Indian 

 and Australian seas ; another very close form described from 

 Chatham Isles east of New Zealand. 



Genus PUFFINUS Briss. 



Puffinus Brisson, On., i, p. 56 (1760 — Type according to vol. vi, p. 130, 

 " Puffinus," i.e. Procellaria puffinus Briinn.). 



Middle-sized Petrels with very long wings and elongated 

 slender bills. The depressed middle portion is about half the total 

 length of bill. Nostrils on top of culmen, well divided and visible 

 from above. Tarsus laterally compressed and with a more or less 

 sharp ridge in front. Tail cuneate, 12 rectrices. Wings pointed, 

 1st or 1st and 2nd developed primaries longest. Over 20 species 

 and a number of subspecies in all oceans. 



Key to species of genus Puffinus. 



r Underside brown . . . . . . .P. griseus, p. 434 



' Underside white with grey-brown area in middle of 



't 



abdomen .... .... P. gravis, p. 429 



Underside entirely or mostly white ... 2 



„ / Larger, wing over 290 mm., bill more or less yellowish P. kuhlii, p. 431 

 \ Smaller, wing under 280 mm., bill dark . . 3 



/ Wing over 200 mm. ..... P. puffinus, p. 422 



\ Wing under 200 mm. ..... P. assimilis, p. 426 



