98 Proceedings of the Royal Physical Society. 
as distinguishing characters:—(1) in D. immutabilis the 
first plumage of the young resembles that of the adult, in 
D. melanophrys the two plumages are different; (2) in D. 
immutabilis the bill is “grey, darker at base, tip blackish- 
brown, base of under mandible pale yellow.” The bill of 
the adult D. melanophrys is yellow, the tip of the upper 
mandible only being often slightly darker All other 
points in Mr Rothschild’s description of D. immutabilis, both 
with regard to colour and measurements, appear to me to 
apply just as well to D. melanophrys. It is evident that 
the two species are very closely allied; if they really are 
“species” is—at all events in this connection—of com- 
paratively subordinate importance; the main thing is, that 
the two forms are separable. The first of the above- 
mentioned marks of distinction, important as it is in itself, 
is, of course, not applicable at the determination of the 
species of the Feerde bird; but with regard to the second, 
the latter bird corresponds exactly with D. melanophrys. 
This point must then be decisive, and, according to my 
Opinion, it excludes all doubt as to the species of the 
Myggenaes Albatross. 
The colouring of the Faroe D. melanophrys is as follows :— 
¢ ad. (May 11): Head, neck, wings, upper tail coverts, 
and entire under surface, white. A well marked, dark 
transocular fascia, in front, over, and behind the eyes; 
this streak extends, in front of the eyes, to a greyish-black 
patch, slightly marked in front and below, where it gradually 
shades into white; over the eyes the streak is black, behind 
them blue-grey, by and by shading into the white colour 
of the head. Back, greyish-black, paler in front, washed 
with bluish-grey, and here gradually shading into the white 
colour of the neck. Quills and wing coverts black; shafts 
1 It is possible that a third mark of distinction might be alleged, viz., 
Mr Rothschild writes of D. immutabilis (loc. cit.): ‘*space in front of the 
eye sooty black,” but does not mention that this spot continues in a streak 
over and behind the eyes. It is not qnite clear to meif from this may be 
inferred, that this stripe is constantly wanting in the Laysan Albatross. 
D. melanophrys has, as is well known, a dark eyebrow stripe, that often 
extends to a spot in front of the eyes; sometimes—but not in the Ferée bird 
—this marking is entirely wanting. 
