Vol. XVII 
1900 
ANTHONY, Westing Habits of Shearwaters. 249 
anything but a pleasure, as one constantly broke through into 
tunnels, the exact location of which it was impossible to determine. 
The tracks in the fresh soil about the entrance to the burrows 
showed the imprint of the tarsus for its full length, showing that 
the birds rest their weight on the tarsus as much as on the toes. 
There was little attempt at nest-building, the eggs for the most 
part being laid in a depression in the sand at the end of the bur- 
row. Ina few cases a number of small twigs and sticks had been 
placed in the hollow forming a very crude nest. Before the egg 
is deposited the burrow is occupied by both birds, and I have 
found them on the nest at least a month before any eggs were 
laid. Just how early they take to the burrows I am unable to 
say, not having visited the nesting colony earlier than the first 
week in March, when all the burrows were occupied. 
I have never heard any love notes from this species when in 
the burrows. Their outcry at night, however, when they emerge 
from their nests and fly about over the island, is something unique 
in my experience. ‘The note isa series of choking cries coupled 
with a hissing, like escaping steam, the same that I have at times 
heard them utter when disturbed in their burrows. On July 1,I 
found the burrows on Natividad occupied entirely by young birds 
that were nearly or quite as large as the adults, but still clothed 
in down through which were growing a few feathers. They were 
sooty black above and lighter below. When brought to the light 
they gave vent to their feelings in the characteristic notes of the 
adults. 
About Cape St. Lucas Townsend’s Shearwater (Pufinus auricu- 
laris) is rather common, and though perfectly distinct specifically 
it is quite closely related to . opfisthomelas and has a similar 
breeding season. On San Benedicto Island I found a few nesting 
the last week in May. At this date most of the young were 
but a few days old, covered with sooty down above, and paler- 
grayish below. With the smaller young I often found one of the 
parents, but they were as frequently alone. The burrows were all 
confined to the higher parts of the island — about 500 feet above 
the sea, where they were dug among the bunches of thick, tangled 
grass, and were well scattered, a dozen or so being a large colony. 
The burrows were not so deep or long as were those of P. of/s- 
