PETREL. NATATORES. THALASSIDROMA. 537 



FORK-TAILED STORM-PETREL. 



THALASSIDROMA BULLOCKII, Mihi. 



PLATE GUI. FIG. 1. 



Procellaria BuUockii, Flem. Br. Anim. 1. 136. No. 219. 

 Procellaria Leachii, Steph. Shaw's Zool. 13. 219. pL 25. 

 Petrel de Leach, Temm. Man. d'Orn. 2. 812. 



THIS Petrel, which is about one-third larger than the pre- 

 ceding, was first discovered at St Kilda, and ascertained to 

 be a distinct species by Mr BULLOCK in 1818, during a tour 

 round the coast of Scotland, principally undertaken with a 

 view to investigate its ornithology. I have, therefore, in 

 imitation of Dr FLEMING, and in justice to the original dis- 

 coverer, adopted the trivial name of Bullockii, instead of 

 that of Leachii, bestowed upon it by TEMMINCK in his 

 " Manuel d'Ornithologie." Several of these birds were found 

 by Mr BULLOCK at St Kilda, it being the season of incuba- 

 tion ; and subsequent observation has shewn that they an- 

 nually resort to the island for this particular purpose. They 

 have also been repeatedly found, within a few years past, in 

 various places inland (like the preceding species) in a dead 

 or exhausted state, among which I may mention two in the 

 possession of the Rev. R. HAMMOND of Swaff ham in Nor- 

 folk, one of which was taken in Gloucestershire, and the 

 other found dead upon a warren in the former county. Sir 

 WILLIAM JARDINE also possesses one, taken in a dying state 

 in Dumfriesshire ; and Mr ELTON of Redland, near Bristol, 

 informs me that four or five were picked up last winter in 

 that neighbourhood, all in a helpless condition. The habits of 

 this bird are similar to those of the Common Storm-Petrel, 

 with which, notwithstanding its superior size, it has in all 

 probability been often confounded when seen upon wing. 

 It breeds in similar situations, laying a single egg of a large Incuba. 

 size, rounded shape, and entirely white. It feeds upon ma- -p ^ t 



VOL. II. M m 



