THE PETREL. 21 
The bird which approaches the nearest to the bank- 
swallow in its manner of breeding is the stormy pe- 
trel (Thalassidroma pelagica, Vicors), the storm- 
swallow of the Dutch, whose great power of wing 
enables it to sweep over the ocean at every distance 
from land, and even to weather the most tempestu- 
ous winds, while with its webbed feet and light form 
it can actually walk upon the billows with as much 
ease aS a sparrow can hop along a garden walk. 
‘It is, indeed, an interesting sight,” says Wilson, 
“to observe these little birds, in a gale, coursing 
over the waves, down the declivities, and up the 
ascents of the foaming surf that threatens to burst 
over their heads, sweeping along the hollow troughs 
of the sea as in a sheltered valley, and again mount- 
ing with the rising billow, and just above its surface, 
occasionally dropping their feet, which, striking the 
water, throw them up again with additional force, 
sometimes leaping, with both legs parallel, on the 
surface of the roughest waves for several yards at 
a time. Meanwhile they continue coursing from 
side to side of the ship’s wake, making excursions 
far and wide to the right and to the left, now a great 
way ahead, and now shooting astern for several hun- 
dred yards, returning again to the ship.as if she were 
all the while stationary, though perhaps running at 
the rate of ten knots an hour. But the most singu- 
lar peculiarity of this bird is its faculty of standing, 
and even running on the surface of the water, which 
it performs with apparent facility. When any grea- 
sy matter is thrown overboard, these birds instantly 
collect around it, facing to windward, with their 
long wings expanded and their webbed feet patting 
the water. The lightness of their bodies, and the 
action of the wind on their wings, enable them with 
ease to assume this position. In calm weather they 
perform the same manceuvre by keeping their wings 
just so much in action as to prevent their feet from 
sinking below the surface.”* 
* American Omithology, vii., 97. 
