The Superior times. [volume] (Superior, Wis.) 1870-1912, 1886-09-11
DOWN IN THE DEPTHS
Animal Lie at the Bottom of the AT. an
10

Inc Kinu, abundance and variety c.
animal life on the ocean bottom are
entirely dependent upon two things:
First, and most important, tempera-
ture; second, depth. Wherever a warm
belt OF water Is encountered, as yeind
beneatb:the Gulf Stream in from 80
to LOO athoms, an abundant fauna
OF tropical character is present. In
the colder waters the animals are
more arctic IL type. Where there are
oeits OF warm and cold water alternat.
ing the fauna Of the one is distinct
from that OF the neighboring belt; so
distinct, IN fact, that we can tell bv
the kind OF animals brought up. when
we are In the cold part, when in the
warm region. Depth does not form
such a powerful dividing line, for the
fauna OF different depths overlap; and
shallow water types, If the temperature
permits, are frequently taken in very
deep water. There is, however, q
gradual and marked transition from
shore through shallow water to the
very deep water forms.
The bottom temperature south of
New England forms a most interesting
study, representing as it does, so many
novel conditions. From the shore the
temperature gradually falls until sixty
fathoms Is reached, and here the warm
belt begins. At 200 fathoms the tenn
perature again begins to fall, as the
depth increases, until the deepest wa
ter Is reached. In August the plateau
at depth OF sixty fathoms, has a
temperature of 81 Fahrenheit, and
then in winter no doubt descends be-
low 800. Inhabiting this region there
Is fauna in all respects arctic in type:
and, indeed, frequently at this depth
we find specie ghich inhabit the
shore OF Labrador. This fauna resem-
bles very closely the fauna north OF
Cape Cod and on the European coast.
The Gulf stream begins just above the
sIxty-fathom line, appearing first as a
slightly warmer stratum of water
few fathoms below the surface. For
this reason the inner edge of the Gulf
Stream Is nearer shore than is marked
on the charts. On the surface it is not
telt for several miles beyond this. The
influence or the Gulf stream is mani
tested through depth of l so fathoms,
so that from IS to $50 fathoms the
bottom waters are uniformly warm
because OF this influence. The bottom
temperature here throughout the en-
tire year Is from 49, to 500 Fahren-
helt. From the $50 fathOm line, as
the depth increases the temperature
decreases even to the greatest ocean
depth; in 500 fathoms being about
400, and $500 $50. Thus wehavea
warm belt less than twenty miles in
width, of q depth varying from 65 to
100 faUhOms, which extends along our
coast from the West Indies past Flor
ida, where it is but few miles wide,
nearly to the region of Nova Scotia,
where it is eliminated by the more
powerful polar currents. On leach side
OF this belt there is q region of colder
water, so cold that the animals are
practically arctic.
lnhablting the inner region the ami
mails, as mentioned above, are COM
mon types, many of which are North
ern-shore forms. But in the warm
belt, which was discovered in 1880,
nearly all the animals were found to
be new to our coast. They were trop-
ical in most respects and proved to be
an extension OF the West Indian Gulf
Stream fauna. Two hundred new
species were obtained and others new
to our coast, some of them being iden-
tical with fossil species from the
Quarternary deposits IN Italy and
Others with species dredged in the
Mediterranean. Those from the deep
er waters are OF types peculiar to the
water of the great ocean depths and
usually unlike any shoreforms. They
q, I'd al or
ture and belong rather to types long
since supposed to be extinct and now
represented only in fosslliferous rocks,
than to anything known to live else
where than in the deep sea.
The bottom mud contains q large
percentage of tests of foraminifera,
microscopic animals, which belong to
the lowest group of animal life-the
Protozoa. They are one-celled and
simple, but covered IN most cases with
calcareous tests of marked beauty and
variety of shape. When examined
with q microscope these tiny shells
are seen to be of numerous delicate
and pretty colors, some snow white,
others gray, some chocolate brown,
and one kind an exceedingly beautiful
shade OF pink. In form they are
varied, some being spherical, Others
cooled, tubular, crOss-shaped, and some
made up of q mass OF lobes upon
lobes. It has been supposed that most
of these forms live upon the surface,
and only after death drop to the bot
tom; but | believe, for several reasons,
that, although large number do live
on the surface, the large majority live
and die in the depths Of the sea. This
continual rain of dead shells from the
surface added to the large number OF
tests naturally dying on the bottom,
has so influenced the character OF the
bottom mud as to render it decidedly
calcareous. A large number of the
shells become disintegrated, but many
remain whole or only partly broken.
How deep down this deposit OF Glob-
ergerina 0oze, as it is called, extends,
we have, at present, no means OF de-
terminating. Covering this muddy
ooze we find large variety OF very IN
teresting animals, belonging to all the
marine groups. There are brilliant
colored sea anemones in abundance,
all possessed of deadly stinging pow
ers, which they no doubt use on the
curious fishes inhabiting the ocean
bottom. We find bright red star
fishes, crabs, and corals; in fact nearly
all the bottom animals are brilliantly
colored.
Most animals of sufficiently high or
ganization, from all depths greater
than 500 fathoms, have well-devel-
oped eyes, though some are blind;
This is the case with q fish and several
crustaceans which have no external
traces of eyes left. From this it seems
that there must be light of some kind
even in the great depths OF 2, 500 faith
oms, for nature supports no useless
organs, and if there was no light the
eyes of all would become useless and
be lost. 1t is then, without doubt,
true that there is not absolute dark
ness on the bottom of the sea.
Whether sunlight penetrates or not,
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