water, which stand at different heights, and appear as if artificially
excavated. Small streams of water, flowing underground, complete the
disorganization of the vegetable matter, and consolidate the whole.
The climate of the southern part of America appears particularly
favourable to the production of peat. In the Falkland Islands almost
every kind of plant, even the coarse grass which covers the whole
surface of the land, becomes converted into this substance: scarcely
any situation checks its growth; some of the beds are as much as twelve
feet thick, and the lower part becomes so solid when dry, that it will
hardly burn. Although every plant lends its aid, yet in most parts the
Astelia is the most efficient. It is rather a singular circumstance,
as being so very different from what occurs in Europe, that I nowhere
saw moss forming by its decay any portion of the peat in South America.
With respect to the northern limit, at which the climate allows of that
peculiar kind of slow decomposition which is necessary for its
production, I believe that in Chiloe (lat. 41 to 42 degs.), although
there is much swampy ground, no well-characterized peat occurs: but in
the Chonos Islands, three degrees farther southward, we have seen that
it is abundant. On the eastern coast in La Plata (lat. 35 degs.) I was
told by a Spanish resident who had visited Ireland, that he had often
sought for this substance, but had never been able to find any. He
showed me, as the nearest approach to it which he had discovered, a
black peaty soil, so penetrated with roots as to allow of an extremely
slow and imperfect combustion.
The zoology of these broken islets of the Chonos Archipelago is, as
might have been expected, very poor. Of quadrupeds two aquatic kinds
are common. The Myopotamus Coypus (like a beaver, but with a round
tail) is well known from its fine fur, which is an object of trade
throughout the tributaries of La Plata. It here, however, exclusively
frequents salt water; which same circumstance has been mentioned as
sometimes occurring with the great rodent, the Capybara. A small
sea-otter is very numerous; this animal does not feed exclusively on
fish, but, like the seals, draws a large supply from a small red crab,
which swims in shoals near the surface of the water. Mr. Bynoe saw one
in Tierra del Fuego eating a cuttle-fish; and at Low's Harbour, another
was killed in the act of carrying to its hole a large volute shell. At
one place I caught in a trap a singular little mouse (M. brachiotis);
271