IF'
the land it rests upon, and presenting fossihferous strata that we beheve are deposited at even
greater depths ? Ou the other hand, referring to the island under consideration, as it now
appears, we may regard it as the remains of some far more extended body of land. Position
in longitude in the Southern Hemisphere appears to determine the amount of vegetation
an island may possess. Of this we have an instance in South Georgia, aud the reason
is erident; the extension of the great continents is in longitude, and the climate and other
featm-es of the islands depend upon their proximity to the land, which modifies the desolating
infiiience of the icy ocean. The time -we have granted for the formation of the various strata
composing Kerguelen’s Land and the forests that successively decorated them, is sufficient for
the destruction of a large body of land to the northward of it, of which St. Paul’s Island and
Amsterdam Island may be the only remains, or for the subsidence of a chain of mountains
running east and west, of which Prince Edward’s Island, Marion, and the Crozets are the
exposed peaks. IVith regard to the botanical characteristics of Kerguelen’s Land, fidl notices
of them have heen prepared for Sir James Ross’s narrative of the Antai'otic voyage, and the
subject utU be further treated in a work devoted to the distribution of vegetation in the
southem regions.
The Islands of St. Paid and Amsterdam, hitherto ranked under no geographical or botanical
regions, perhaps demand notice here. Though constantly sighted by oiitward-bound
Indiamen and Austraban ships, they have been rarely visited, and never by scientific persons,
except those accompanjring Lord Macartney’s embassy to China, and very recently by my
former companion and zealous cooperator in ad scientific pursuits, Lieut. A. Smith, R.N.
Some confusion stdl exists -with regard to the names of these two islands, which are situated
north-west of Kerguelen’s Land, in the longitude of 78°, and the respective latitudes of 38°
and 39°. The names of St. Paid and Amsterdam have been applied indiscriminately by various
navigators, the latter I continue to give to the southem island, in accordance with Sir George
Staunton’s and vdth the recent south circumpolar charts, where, however, the southernmost
island is represented as the larger instead of the smaller of the two. Both are no doubt of
volcanic origin, though only Amsterdam is in a state of activity. The latter alone has been
risited by Sir G. Staunton, who has published an exceUent account of it, and by Lieut. Smith
who had the kindness to fom-ard me most interesting particulars regarding it, and a collection
of all the plants he was enabled to detect there. No one reading Sir George Staunton’s account,
and especially after looking at his plans and sketches of Amsterdam Island, can fad to
be struck -with the simdarity its most remarkable features present to those of Deception Island,
one of the South Shetlands. They are of the same size; both are annidar craters, open to
the eastward, inclosing a deep lagoon with a conical hiU on each side of the entrance; that at
the northern end being the highest, and both are nuclei of heated matter, with a thin covering
of sod, through which escape streams and springs of warm or boiling water. The general
natm-e ot the vegetation of Amsterdam Island is described by Mr. Smith to be a coarse tufted
grass, which springing from a bed of fine black peat composed of decomposed fibrous vegetable
matter, everywhere covers a soil so heated that the roots cannot descend beyond a few inches.
Sir G. Staunton mentions that changes in the level of the land at the mouth of the cove have
occm-red since 1697, when the island was landed upon by Van 'Vlaming, a Dutch commander
Since 1793, the period of Sir G. Staunton’s visit to the island, half a century has elapsed, and
the changes, if any, have been insignificant. The land may possibly be rising, though according
to Van Vlandng it must have sunk since his time, when there was no communication
between the sea and the lagoon, the intermediate causeway being at least five feet high.
Staunton states the depth of water on the bar to be eight feet at high water, and Lieut. Smith
as 7 ft. 4 in. at the highest springtides. Nor does the temperature of the hot springs appear to
have altered materially durffig the last fifty years, it then averaged 190°, and Mr. Smith found
one that he tried to be 182° (though there are others where the temperatm-e rises to 212^ ; the
latter gentleman boded both fish and rice in one of these springs close to the ocean’s edge
and they were well cooked in twelve minutes, thus confii-ming Sh- G. Staunton’s anecdote,
that a person who had caught fish in the cold water of the lagoon coidd, ndth a slight motion
of his hand, let it di-op into a hot adjoining spring, when it woidd be boded in fifteen minutes
fit for eating (McCartney’s Embassy, vol. i. p. 212), an account that has been treated as
fabulous.
The island of St. Paid, only fifty mdes farther north, has never been visited by a naturalist
; it is mentioned by several authorities as low and imdidating, covered with trees and
shrubs, but with no traces of internal heat; Labfflardiere, who passed this island in 1792,
describes it as being in a state of combustion, but he doubts whether the fires were kindled
by the hand of man, or were owing to subterranean heat. The former is most probably the
case, for Mr. Smith, who lost no opportunity of gaining information about these curious
islands, gives me the foUoiring statement, obtained from some sealers who had visited St.
Paul’s. “ A variety of plants grow luxuriantly in the northern of these two islands, and trees
several inches iu diameter; there are no hot springs there, nor is its earth at all heated;
vegetables may be cultivated udth tolerable success ; but this island is always most difficidt
to land upon.” This precisely tallies vrith other scattered notices of St. Paul’s that I have
seen.
I shall conclude this long digression with a notice of the vegetable productions of Amsterdam
Island. Sir G. Staunton mentions a Lycopodium, a Marchantía, and a long grass; to
these I can now add another species of grass, a Plantago, Colobanthus, an Azorella ? (or Ranunculus
?) a Cenomyce, and several species of Mosses. The Colobanthus is t}-pical of a southern
or Antarctic Flora; but the grasses appear more characteristic of a warmer chmate; from
these materials I do not feel justified in referring the vegetation to any botanical region, but
consider it probable that there may be a considerable proportion of forms indicative of a warm
latitude, especially in St. Paul’s.
The niunber of species in the present Part precludes the introduction of lengthened
descriptions, even were these as reqidsite as I deemed them in the case of the more novel
2 Y