es
of Rubus, the pungent-leaved Epacrideae and a few others."

Mr. J.G. Baker of Kew, who has specially studied the flora of Mauritius
and the adjacent islands, also writes me on this point. He says: "Taking
Mauritius alone, I do not call to mind a single species that is a
spinose endemic tree or shrub. If you take the whole group of islands
(Mauritius, Bourbon, Seychelles, and Rodriguez), there will be about a
dozen species, but then nine of these are palms. Leaving out palms, the
trees and shrubs of that part of the world are exceptionally
non-spinose."

These are certainly remarkable facts, and quite inexplicable on the
theory of spines being caused solely by checked vegetative growth, due
to weakness of constitution or to an arid soil and climate. For the
Galapagos and many parts of the Sandwich Islands are very arid, as is a
considerable part of the North Island of New Zealand. Yet in our own
moist climate and with our very limited number of trees and shrubs we
have about eighteen spiny or prickly species, more, apparently, than in
the whole endemic floras of the Mauritius, Sandwich Islands, and
Galapagos, though these are all especially rich in shrubby and arboreal
species. In New Zealand the prickly Rubus is a leafless trailing plant,
and its prickles are probably a protection against the large snails of
the country, several of which have shells from two to three and a half
inches long.[210] The "wild Spaniards" are very spiny herbaceous
Umbelliferae, and may have gained their spines to preserve them from
being trodden down or eaten by the Moas, which, for countless ages, took
the place of mammals in New Zealand. The exact use or meaning of the
spines in palms is more doubtful, though they are, no doubt, protective
against some animals; but it is certainly an extraordinary fact that in
the entire flora of the Mauritius, so largely consisting of trees and
shrubs, not a single endemic species should be thorny or spiny.

If now we consider that every continental flora produces a considerable
proportion of spiny and thorny species, and that these rise to a maximum
in South Africa, where herbivorous mammalia were (before the settlement
of the country), perhaps, more abundant and varied than in any other
part of the world; while another district, remarkable for well-armed
vegetation, is Chile, where the camel-like vicugnas, llamas, and
alpacas, and an abundance of large rodents wage perpetual war against
shrubby veg