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150 NOTES ON RANGE IN DEPTH OF MARINE ALG^E.
kaliformis, Melobesia calcarea, Rhodymenia cristata, Phyllophora rubens,
P. Brodim, Peyssonelia Dubyi, ahd species of Belesseria. Several of
these are also found in the littoral zone.
It is of interest, however, to ascertain the absolute limit of vegetable
life on our own shores, and the only case which has come under my
own notice is the following :—About ten years ago, in company with
the late Mr. Hyndman, of Belfast, and Mr. Waller, when dredging
near the Maiden Hocks, coast of Antrim, our dredge got fast on rocky
bottom at a depth of about 80 fathoms. With some difficulty we re-
covered it. On examination it contained a few mollusca, abundance
of living zoophytes,* and two red Al(jf2, the largest being Phyllophora
Bi'odiai, quite fresh and of the usual colour. It appeared to have
been recently torn from its site ; still, as it is not unfrequently cast
upon the Antrim coast, it is just possible that the specimen may have
been loose and accidentally entangled in the dredge. Regarding the
other species, I have no doubt it was attached near the base of one of
the living zoophytes ; and, although not more than a quarter of an
inch in length, it could be referred to Bdemeria sinuosa, a species very
widely distributed along the British and Irish shores.
In vol. ii. page 464 of the ' Antarctic Flora,' Dr. J. D. Hooker
states that " 8 to 10 fathoms are the utmost depth at which, judging
by our experience, submerged seaweed vegetates in the South Tempe-
rate and Antarctic Ocean." This may be the general limit, but Macro-
cystis pyrifera is reported, in the same work, as attached to the bottom
ill 40 fathoms, though most of the very long stem—700 feet—lies near
the surface. Lamouroux speaks of the Akja growing at 100 or 200
fathoms, but the statement is more than doubtful. Humboldt records
Puciis vitlfolius {Caulerpa vitifoUa, Lamx. ; Chaiwinia vitifolia, Kiitzing),
as growing in 30 fathoms, and quite green. In ' Nereis Americana,'
Anadyomene stellata is stated to grow in 30 fathoms, and of the usual
green colour, in the Gulf of Mexico. In his report on the vEgean Sea,
the late Professor E. Forbes states that Coristantinea reniformis, P. and
11., occurs at 50 fathoms, and he considered this as the greatest depth,
accurately observed, at which AlgrB vegetate. In a recent number of
* It may be interesting to state the s]iecies : Sertularia abietina, S. ruyosa,
S. aryeidea, S. rosacea, Tubularia indhiisa, T. Larynx, Tulalipora serpens,
Halecium Beanii, Fluslra avicularis, Crisia elurnea, Laomedea .'', and
Caryophyllia Smilhii. The latter hved in an aquarium for nearly two years
after.
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