Petrels from the North-East Pacific Ocean. 585 



genera utilised by Matliews, and we now go more into 

 detail with regard to the relationships of the species. All 

 the species are uniform above and below or white below, 

 save P. leucomelas Avhieh has the head curiously streaked. 

 For this species we are providing a new generic name. 

 Colour considerations alone would suggest its separation 

 from the remainder of the group. It will be discussed in 

 detail later, so we would generally note the distribution of 

 these genera and species and draw attention to some 

 interesting facts. 



Beebe has recently divided the Pheasants into many 

 genera, concluding that no two species of the same genus 

 inhabit the same territory. We welcome such a revolutionary 

 conclusion with gratitude, as the study of sea-birds has en- 

 forced this fact upon us, but we should not have dared to put 

 this before the ornithological world in the deliberate manner 

 Beebe has done. Now that Beebe has opened this matter, 

 we put forward our proposals with contidence. We will 

 use the name " Pufjinus " in the sense of the ' Monograph/ 

 and note that it is really what Beebe calls a supergenus. 

 We are, and have been, continuing investigations with 

 regard to the supergenera of birds, and would scarcely 

 regard " Pi/^WMS " of the 'Monograph^ as a homogeneous 

 supergenus, but for the present it can be so considered. 

 We will only use species-names here. 



On the Kermadecs live : 



Puffinus pacificvs. Genus Thyellodroma. 



assimilis. Alphapuffinus. 



On Lord Howe Island live : 



Paffi,7ius pacificus. Genus Thyellodroma. 



carneipes, Hemipiiffinus. 



assioiilis. AIphapt(,ffi?ms. 



On Norfolk Island live : 



Puffinus pacifcus. Genus Thyellodroma. 



assimilis. Alphapvffinus. 



