e been noted, the most interesting being the discovery of no
less than three American species of fresh-water sponge, which are
unknown in the rest of Europe.

To account for the presence of this American group naturalists are
driven, as in the case of the southern species, to the conclusion that
these represent one of the very oldest components of our existing fauna
and flora, and point to a period when the edge of Europe was prolonged
far to the north-west, forming a continuous land area, presumably by way
of Iceland and Greenland, to America. And here on the wild western coast
of Ireland these last inhabitants of the lost lands of Europe still
survive.

[Illustration: The Kerry Slug, showing the manner in which its
coloration mimics clusters of lichen among which it lives.]

[Illustration: _Photo, Welch, Belfast._ Nest of Wood Ant at Killarney]

4. ~CLARE AND EAST GALWAY.~--Our last district--West Cork and Kerry--was
characterised by great ribs of slate and sandstone, and by an absence of
limestone and the numerous plants which follow in its train. The present
district forms a marked contrast, being largely composed of
Carboniferous limestone. And the remarkable thing about these limestones
is that they are over many miles totally devoid of any covering of soil
or clay; the grey gnarled rock, fantastically carved and crevassed by
the action of rain and weather, lies naked and bare. But in the crevices
of the rock a wonderful variety of rare and beautiful plants abound. One
or two of these have their home in the far south, like the plants we
have lately considered, notably the little Close-flowered Orchid,
_Neotinea intacta_, whose nearest station is about Nice. But the
majority of the interesting species of these limestones are alpine
plants, usually found at high elevations on mountains, which here form
sheets of verdure down to the very edge of the sea. The Mountain Dryas
(_D. octopetala_), the Bearberry (_Arctostaphylos Uva-ursi_), the lovely
Spring Gentian (_G. verna_), and the Blue Moor-grass (_Sesleria
caerulea_) are good examples, all of them growing in great abundance from
the hill-tops down to the shore. It is this strange mingling of plants
from the far south, from the far north, and from the mountains, which
renders the West of Ireland so fascinating a field for the botanist. In
the barren district of Clare, and in the adjoining Isles of Arran and
south-west portion of county Galway, this peculiar flora