’
—
THE SEA BQTTOM
7n
strange shapes like the whitened boues of some prehistoric
monster
'
'
'
‘
-
…
ABYSSAL ZONE
,
.
,
g
the remarkable conditions there prevailing, the ‘
inhabitahts of the Abyssal zone are quite unlike those‘ of the
Continental Shelf, far fewer in numbers and quite different
in appearance. The Continental Slope which connects these
two régions is seldom trav—ersed by animals passing from the
one Zone to the other for the Conditions in the greatdepths
are such that its inhabitañts have to be very specially
.
equipped for life and are unable to' adapt themselves to —
existence in shallower water.
Conditions are more
uniform
in the abyss than on any othérpart of the earth’s surface.
There is absolute darkness; an unchanging temperature
only slightly above zero and an enormouspfessure amount—
ing,
of three thousand fathoms, ‘_to about three
tons per
inch.
There is rio-vegetation and no exposed
rocks, everything being covered with alayer of soft ooze.
.
The place of attached animals is taken by creatures with
long stalks, which lift their bodies clear above the mud.
'
Examples are provided by the-sea lilies
5), closely
'
related to the feather—'st‘ars of
Water but with a
long stalk in place of the short root-like butgrôwths,
by the sea pens, here at their most abùndant,‘ some
alcyonarian corals, sponges, sea squirts and sea mats.
Many of the crustaceans have long legs for lifting their
bodies above the mud, _and so have the sea. Spiders Which
may have li1nbs two feet long » (Plate 25).- There are
'
relatively few animals with calcareous skelet0ns, molluscs,
.
especially bivalves, being particularly rare, though some
interesting examples of the latter which, unlike their shallow
water relatives,have become carnivorous, arefound in the
.
greatest depths.
The total darkness has =”re‘sùlted,_
—
THE SEA BQTTOM
7n
strange shapes like the whitened boues of some prehistoric
monster
'
'
'
‘
-
…
ABYSSAL ZONE
,
.
,
g
the remarkable conditions there prevailing, the ‘
inhabitahts of the Abyssal zone are quite unlike those‘ of the
Continental Shelf, far fewer in numbers and quite different
in appearance. The Continental Slope which connects these
two régions is seldom trav—ersed by animals passing from the
one Zone to the other for the Conditions in the greatdepths
are such that its inhabitañts have to be very specially
.
equipped for life and are unable to' adapt themselves to —
existence in shallower water.
Conditions are more
uniform
in the abyss than on any othérpart of the earth’s surface.
There is absolute darkness; an unchanging temperature
only slightly above zero and an enormouspfessure amount—
ing,
of three thousand fathoms, ‘_to about three
tons per
inch.
There is rio-vegetation and no exposed
rocks, everything being covered with alayer of soft ooze.
.
The place of attached animals is taken by creatures with
long stalks, which lift their bodies clear above the mud.
'
Examples are provided by the-sea lilies
5), closely
'
related to the feather—'st‘ars of
Water but with a
long stalk in place of the short root-like butgrôwths,
by the sea pens, here at their most abùndant,‘ some
alcyonarian corals, sponges, sea squirts and sea mats.
Many of the crustaceans have long legs for lifting their
bodies above the mud, _and so have the sea. Spiders Which
may have li1nbs two feet long » (Plate 25).- There are
'
relatively few animals with calcareous skelet0ns, molluscs,
.
especially bivalves, being particularly rare, though some
interesting examples of the latter which, unlike their shallow
water relatives,have become carnivorous, arefound in the
.
greatest depths.
The total darkness has =”re‘sùlted,_