NATATOUES. 477 



will therefore easily imagine with what pleasure I descended 

 the ship's side and sallied forth in a little ' dingy ' to procure 

 specimens. This is not the only instance in which science 

 has been benefited through the kindness of the captains I 

 have sailed with in allowing me the use of a boat whenever the 

 weather permitted such a favour to be granted me without 

 retarding the progress of the ship. Nearly thirty species 

 of oceanic birds were obtained in this way during my voyage 

 to Australia; whence some idea may be formed of the 

 numbers encountered in the open sea, and of the employment 

 the naturalist may find during a voyage round the globe. 



In the habits and mode of flight of this species I could 

 observe no difference whatever from those of the other Storm- 

 Petrels ; and, as a matter of course, its food is also similar ; 

 any oily substance, together with mollusks, being equally 

 partaken of by all the members of the genus. 



I did not observe this species in any other parts of the 

 ocean than those mentioned above ; at the same time it is not 

 improbable that it may possess a much wider range. 



The sexes are alike in plumage, and are not materially 

 different in size. 



Head, neck, and chest sooty grey ; lower part of the wing- 

 coverts, back, rump, and upper tail-coverts grey, each feather 

 very slightly margined with white ; wings greyish black ; tail 

 grey, broadly tipped with black ; under surface pure white ; 

 irides, bill, and feet black. 



Total length 6^ inches ; bill -j^ ; wing" 5 J ; tail 2 J ; tarsi 1| . 



Note. — It would be well if naturalists accompanying expe- 

 ditions to the South Pacific and South Indian Oceans were 

 to collect examples of this species, as but few of our museums 

 possess it. 



