adows, and state that they retarded the
progress of their vessels. The most extensive bank is a little west of
the meridian of Fayal, one of the Azores, between latitudes 35 degrees
and 36 degrees: violent north-winds sometimes prevail in this space, and
drive the sea-weed to low latitudes, as far as the 24th or even the 20th
degree.[859] Along the northern edge of the Gulf stream Dr. Hooker found
_Fucus nodosus_, and _F. serratus_, which he traced all the way from
lat. 36 degrees N. to England.

The hollow pod-like receptacle in which the seeds of many algae are
lodged, and the filaments attached to the seed-vessels of others, seem
intended to give buoyancy; and I may observe that these hydrophytes are
in general _proliferous_, so that the smallest fragment of a branch can
be developed into a perfect plant. The seeds, moreover, of the greater
number of species are enveloped with a mucous matter like that which
surrounds the eggs of some fish, and which not only protects them from
injury, but serves to attach them to floating bodies or to rocks.

_Agency of animals in the distribution of plants._--But we have as yet
considered part only of the fertile resources of nature for conveying
seeds to a distance from their place of growth. The various tribes of
animals are busily engaged in furthering an object whence they derive
such important advantages. Sometimes an express provision is found in
the structure of seeds to enable them to adhere firmly by prickles,
hooks, and hairs, to the coats of animals, or feathers of the winged
tribe, to which they remain attached for weeks, or even months, and are
borne along into every region whither birds or quadrupeds may migrate.
Linnaeus enumerates fifty genera of plants, and the number now known to
botanists is much greater, which are armed with hooks, by which, when
ripe, they adhere to the coats of animals. Most of these vegetables, he
remarks, require a soil enriched with dung. Few have failed to mark the
locks of wool hanging on the thorn-bushes, wherever the sheep pass, and
it is probable that the wolf or lion never give-chase to herbivorous
animals without being unconsciously subservient to this part of the
vegetable economy.

A deer has strayed from the herd when browsing on some rich pasture,
when he is suddenly alarmed by the approach of his foe. He instantly
takes to flight, dashing through many a thicket, and swimming across
many a river and lake. The seeds of the herbs