WHITE BELLIED STORM-PETREL. l5‘ 
close-CTOwing ice-plant. It was very unpleasant walking oyer 
these breeding-grounds, which occupied considerable areas, for 
the ground was honeycombed with burrows in every direction, 
and gave way at each step, one’s boots rapidly becoming full 
of sand. By thrusting our arms into one hole after another, 
we soon procured a fine series of specimens, accoinpanied m 
most cases by an egg, for we had evidently hit off the breeding 
season, and most of the birds, having laid their single egg, 
W'ere beginning to sit. Both sexes take part in incubation, tor 
out of twelve birds captured on the egg three were males. 
While thus engaged we found quite a number of dead birds 
and sucked eggs, evidently the work of the mice, as their 
droppings were to be seen all about the burrows, and the 
marks of their teeth upon the empty shells were unmis- 
takable. The birds, some of which were quite freshly 
killed and almost untouched, were invariably done to death by 
being bitten at the nape of the neck, and in some cases part 
of the brain had been eaten. It seemed curious that these 
comparatively small mice should be able to kill a bird several 
times larger than themselves, and provided with a fairly strong 
hooked bill ; but no doubt the Petrels get caught in the end 
of their burrow, and, being terrified, do not even try to defend 
themselves. We obtained no young of this species, and the 
most advanced eggs were but half incubated on the 27th of April. 
We never heard the call of this bird ; those flying over the sea 
during the daytime were always perfectly silent so far as we 
heard, though they constantly passed close to our tug, and 
there was no lack of them. \Vhen caught on their eggs they 
uttered a short, grunting note, much like that given vent to by 
the domestic Pigeon under similar circumstances. Our Lan- 
zarote pilot informed us that numbers of these birds breed on 
the Little Piton, where there are neither rats nor mice to inter 
fere with them.” 
Nest. — None. The egg being laid in a sandy burrow. 
Eggs. — One. White, with tiny reddish or purplish dots, 
sprinkled all over the surface, or forming a zone round the 
larger end. Axis, 1-45 inch; diam., i'o5. 
