MONOGRAPH OF THE PETRELS. 



character for distinction to be the black band round the edge of the wing (Ibis, 1905, 

 p. 554). 



Salvin pointed out that the upper-parts of (E. cervicalis are much darker than those 

 of (E. externa, and this is the case in adult birds, though in our series from the Kermadecs 

 there are some examples, evidently young birds, nearly as light as the type of 

 (E. externa. There are also two specimens before me, one of each species, with the 

 down still upon them, and in both the feathers on the back and upper wing-coverts are 

 paler and broadly margined with grey; these characters are evidently therefore an 

 indication of youth. 



(E. cervicalis is, so far as is known, confined to the Kermadec Islands. Mr. 

 Cheeseman says (Tr. New Zeal. Inst., XXIII., pp. 216 and 226) that the bird arrives 

 about the end of September and remains till the end of June, being one of the last 

 Petrels to leave. Its breeding-place is usually near the mountain-top in some dark 

 gully filled with palms and tree-ferns, amongst the roots of which the burrow is generally 

 made. It is nocturnal and solitary in its habits, more than one nest being seldom 

 found in the same locality. An egg sent to the Auckland Museum by Mr. Day 

 measured 2.5 inches in length, and 1.9 inch in breadth, and was pure white. 



Having examined large series of this species, I consider that (E. cervicalis and (E. 

 externa must be recognised as distinct, the more so as their habitats are so far 

 apart from each other, and they have not been found in any intervening locality. 

 Compared with (E. externa, (E. cervicalis is darker on the head and back, the tail-feathers 

 are much lighter below, the two outer rectrices being for the most part white, while the 

 marginal under wing-coverts are either entirely black or mottled with black. 



In our figure of this bird the feathers of the upper-back and the greater series of 

 coverts have been drawn rather too dark, as these parts generally have greyish margins 

 to the feathers, the coverts likewise being fringed with hoary-white. These are 

 characters which obtain in the majority of specimens, and the darker birds, such as the 

 one figured, are by no means so common, but are probably the most fully adult. 



Adult (type of species). General colour above black, shaded with grey, and having 

 slaty-grey edges to all the feathers of the upper-parts, excepting the scapulars and 

 wing-coverts, which are black ; the greater wing-coverts black, shaded with grey, and 

 edged externally with slaty-grey, and with hoary-white near the ends ; bastard-wing, 

 primary-coverts, and quills black, the primaries ashy-brown on the inner web, which 

 is white for a considerable distance from the base ; secondaries externally slaty-grey, 

 with a narrow fringe of hoary-white, like the greater wing-coverts, the innermost 

 secondaries black like the longer scapulars ; lower back and centre of rump black ; 

 sides of rump and upper tail-coverts slaty-grey, with black shaft-lines and paler ashy 

 edges at the end of the feathers ; centre tail-feathers slaty-black, the lateral ones slaty- 

 grey externally, and white on the inner web, which is freckled with grey at the end ; 

 crown of head black, the nape-feathers white with black tips ; hind-neck and sides of 



224 



