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CHAPTER V
_
.
'
Drifting Life
"
WE have dealt so far with those animals and plants which
_
live either on the sea bottom, or swimming activelythrough
the water above the bottom.
There is yet another com—
munity of organiSms in the
existence is, perhaps,
,
not generally realized.
It consists of countless numbers of
animals and plants which drift about in the water layers
at all depths betweenthe sea surface and the bottom, at the
_
mercy
of tide and current._ They are nearly all small,
_
most of them minute, and many only visible, under the high—
powered
It is extremely
demonstrate theirpresence; it is
merely necessary to drag through the sea for a few minutes ‘
asmall cone—shaped net, or ‘_‘ tow-net” (Plate 96), made
'of ne muslim, cheesecldth or Silk ; or, if one is on an ocean
liner, it is even possible to obtain them"by hanging a small
,
muslim bag under the salt-water tap in the bathroom, and
'
just letting the water run.
.
At times this drifting life is so abundant that it colours
the
sea
for
miles
around.
Such
expressions as
red
water,”
“
yellow
and “
are
used by
_
shermen, who become wonderfully expert at- deciding
where 'to shoot their mackerél or pilchard nets by slight
differences. in the tint of the water that laridsmen would
not notice.
every Case the characteristic tinge given
Î
to_theseais known to be due to the presence of certain
kinds oforgaisms in innumerable quantities. ‘ Darwin
.
no
,