This plant is dispersed almost over the whole explored ocean,
having been brought from nearly every shore, except those few
antarctic coasts where nothing marine vegetates, save Diatomacea.
I have never seen a collection of Algse, of any extent, from any
part of the world, which did not contain specimens of Enteromor-
plia compressa. Though always recognizable by the character of
its branches tapering toward the base, it puts on a multitude of
aspects according to the situation in which it grows. Near high-
water mark it forms a short, shaggy pile, of slender fronds,
spreading over rocks and stones, and most treacherous to the
stepping of unwary feet, being pre-eminently slippery. A little
lower down, in the rock-pools, it has the appearance of the varieties
figured in our plate ; and where fresh-water streams flow
into the sea, it becomes broader, with inflated tubes, and often
of great length. Such forms closely resemble E. intestinalis,
which, however, is never branched. Other varieties occur on
floating timber, on piles exposed to the tide, and on the vertical
. walls of quays in tidal rivers ; in fact, in nine cases out of ten,
when such objects are seen clad in green, the appearance is
caused by the presence of this species.
Fig. 1. Sundiy varieties of E n t e r o m o r p h a c o m p r e s s a ;— o f the
3. A small portion of a branch magnified, to show the cellular structure.