BULWER'S PETREL. 665 



as well as some differences in their habits, which will ap- 

 pear in their histories. Those who have an opportunity of 

 examining and comparing the skeleton of our Manx Shear- 

 water with that of the Storm Petrel, cannot fail to observe 

 internal distinctions also ; that of the Manx Shearwater 

 possessing the sternum, and low keel of a swimming and 

 diving-bird ; the Storm Petrel, on the other hand, exhi- 

 biting the deep keel of a Swift, and possessing accordingly 

 enduring powers of flight. These birds form M. Tem- 

 minck's third section of the genus Procellaria, which sec- 

 tion has been advanced to generic distinction in the fourth 

 part of M. Temminck's Manual. The term Thalassidroma 

 refers to the power and habit of this group of running on 

 the surface of the sea. 



The first published notice of Bulwer's Petrel that I am 

 acquainted with, is that by Sir William Jardine and Mr. 

 Selby, in the second volume of their Illustrations of Orni- 

 thology, already quoted. 



" We are indebted to the kindness of Mr. Bulwer, 

 during some years a resident in Madeira, for the subject of 

 this plate, which we consider as yet undescribed. It is not 

 to be found in the works of Latham or Shaw, or indeed in 

 any other which we have had an opportunity of consulting ; 

 and, from its marked characters, it is not a species that 

 would be easily overlooked. The length of our specimen is 

 about ten inches ; it inhabits Madeira, or the small islands 

 adjacent." 



For its title to a place among our British Birds I refer 

 to Mr. Gould, who, in the 22nd, the concluding, part of 

 his Birds of Europe, gives a figure from a specimen ob- 

 tained in this country, with the following observations : 



" On the authority of Colonel Dalton, of Slenningford, 

 near Ripon, we are enabled to add this rare species to the 

 Fauna of Britain, from a fine specimen which was found on 



