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ALCAD^. 
lived a bird as the Guillemot, and that the declension in point 
of numbers may be accounted for on the principle that the 
adverse influences which have increased with the progress of 
civilisation would tell more in proportion upon the shorter-lived 
bird. The suggestion may at any rate furnish a hint for a 
mathematical examiner inventing a problem paper, and to 
him we will leave it, merely remarking that as the Eazor-bill 
is a good deal bigger than the Guillemot, it j)erhaps offers an 
easier mark to the gunners. It would nevertheless be very 
desirable to get accurate observations on the duration of life 
in birds of this class which lay but one egg, as compared 
with others which lay many. The Eazor-bill arrives and 
departs about the same time with the Guillemot. One of the 
few which I have seen in winter was shot by me at Balta 
Sound on the 17th of December. It was a female, and among 
other signs of adult age it had the bill perfect in form, and 
grooved upon the side, one of the grooves being white. The 
throat and the remainder of the under surface were white, and 
in short the whole plumage was in every respect similar to that 
which is described by various authors as characterising this 
species in winter, with the single exception of there being no 
white line between the base of the bill and the eye. I am at 
a loss to account for its absence ; for, so far as I am able to 
ascertain, such a mark becomes apparent even in young birds 
soon after they leave the rocks, and is distinct during their 
first winter. It seemed well to make a careful note of this, 
from its possible bearing on the question as to the right of the 
“ ringed ” Guillemot to rank as a distinct species simply on 
account of the white lines near the eye. 
The mode of diving in this species is peculiar, the bird dis- 
appearing almost perpendicularly, so that for an instant one 
sees nothing but the tail sticking up above the surface of the 
water. One evening in June a man brought me a Eazor-bill 
which he had caught at the deep-sea fishing a few hours 
before. It had dived after the bait as the lines were being 
hauled in, and was hooked in the breast. 
