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yellow amorphous particles, a few bright-yellow oil-globules, and several ova.
In two specimens examined at a subsequent date, I found the GloMgerinæ,
amorphous particles, and oil-globules as before, but no ova; whilst in the
deposit itself were detected two small Echinoderm-spines which, on comparison,
proved to be identical with those on the arms of the Ophiocomæ.
In three soundings (including that in which the Star-fishes were obtained)
taken in the under-mentioned positions and depths—namely, lat. 59° 27' N.,
long. 26° 41' AV., depth 1260 fathoms; lat. 58° 23' N., long. 48° 50' AV., depth
1913 fathoms; and lat. 56° 43' N., long. 11° 5 5 'AV., depth 1268 fathoms—
minute cylindrical tubes occurred, varying from |t h to | an inch in length, and
from sTjth to -^oth of an inch in diameter. These were built up almost exclusively
of very small Globigerina-shells and still more minute calcareous débris cemented
together. Two or three such tubes were found by me in each of these soundings,
but I failed to extract the animals from them in a sufficiently perfect condition to
admit of identification. I am nevertheless able to state positively that the tubes
contained some species of Annelid, and think it highly probable that certain
borings to be seen on Foraminiferous shells in the same deposits may have been
effected by it. But, whether this be the case or not, it is quite clear that an
Annelid lives at the depths indicated, and there builds up its tenement. The
shells forming the outer layer of the tubes were colourless and freed of all sarcodic
matter ; but the internal surface of the tubular cylinder was lined with a
delicate yet distinct layer of reddish chitine.
I t has been stated that these tubes are almost exclusively built up of Globigerina
shells. The proportion is probably about 98 per cent., the remaining
2 per cent, being made up of Sponge-spicules, Diatom-valves, and minute
particles of other mineral matter.
In a sounding taken in somewhat shallower water, namely, in 871 fathoms,
in lat. 61° 35' N., long. 24° 9' AV. (about halfway between Cape Eekianess and
the position of the Star-fish sounding), I detected two tubes, probably formed by
the same or a closely allied species of Annelid, but differing from the last in the
total absence of Globigerina-shells, and their replacement by nearly equal proportions
of minute calcareous débris and Sponge-spicules. The size of the
tubes in this sounding would appear to be modified by the more compact
“ stowage ” of which their material is capable ; and hence the diameter is
reduced in the two specimens to -rsth and -gVth of an inch respectively,—about
2 per cent., again, consisting of what may be regarded as accidental particles,
namely, fragments of Foraminiferous shells and Diatom-valves.
The importance of these facts can scarcely be overrated; for, although the
presence of Annelid-tubes neither proves the vitality of their occupants nor of
the Foraminifera and Sponges which supplied the material to construct them,
yet, since we know that all tubioolous Annelids are essentially ground-inhabiting
creatures, it is manifest that the tubes must have been built upon the sea-bed,
and hence that the living Annelids must have been there present to build them.
And further, if we admit the connexion between the bored Foraminiferous shells
met with in the same deposits and these Annelids, we must also admit the probability
that the latter found within the bored shells suitable living nutriment
to recompense them for their trouble.
But the material of the tubes supplies its share of valuable evidence likewise;
for we find that whereas in the 1260- and 1268-fathom deposits, which consist
chiefly of Foraminiferous shells, the tubes are formed almost exclusively of this
material, in the 871-fathom deposit, which consists of a nearly equal admixture
of calcareous and siliceous matter, the tubes partake of the same proportions,
clearly showing that, both in the kind and quantity of material employed, the
Annelid is dependent on the character of the deposit on which it lives.
In a sounding taken in lat. 63° 31' N., long. 13° 45' AA^., in 682 fathoms, a
portion of a Serpula-tube, i\th s of an inch in length, and about -A^ths of an inch
in diameter, belonging to a known species, came up in such a condition as to
leave no room for doubt that it had been broken off the rock or stone to which
it was adherent by the sounding-machine, and that the animal was living;
whilst a smaller Serpula a cluster of apparently living Polyzoa were adherent
to its external surface. A minute living SpirorUs also occurred in this sounding.
Lastly, from a depth of 445 fathoms, within a short distance of the south
coast of Iceland, a couple of living Amphipod Crustaceans were obtained, and a
filamentous Annelid about three-quarters of an inch in length.
Bearing in mind, then, 1st, that the GloUgerince have never been detected
free-floating in any number in deep, or forming deposits in shallow water; that
a considerable proportion of those met with in the deep-sea deposits exhibit
every appearance of vitality; that their maximum development is associated with
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