o2 Notices of Memoirs—Dr. R. F. Scharff— 
are quite confined to these continents. Of those which also occur in 
Asia there are many, like the Orchid Lestera cordata, which grows only 
in a few localities in the extreme east, that are apparently absent from 
the greater part of the continent. It is probable that all these have 
found their way from America to Europe by a direct passage. 
Moreover, we know from Professor Drummond’s researches that of 
seventy species of fossil plants observed by him in the Pleistocene 
clays of Toronto in Canada, twenty occur at the present day both in 
that country and in Europe.'' This seems to indicate that during the 
Pleistocene period, the great mass of the flora common to America and 
Europe had already found its way from the one continent to the 
other. 
The zoological testimony in support of this view is of a more 
pronounced character. The interest aroused in Ireland by the 
discovery of the American plants has led to research in other 
directions. Thus, in 1895, three species of freshwater sponges were 
detected in various lakes at some distance from the sea on the west 
coast. Only one of these sponges, viz. Zubella pennsylvanica, has since 
been observed in another European locality, in Loch Baa in Scotland, 
but all of them are identical with American species.” Dr. Hanitsch 
identified them as Hphydatia crateriformis, Heteromeyenia Ryder, and 
Tubella pennsylvaniea. 
In my more recent work on European Animals, I have incidentally 
dwelt on the past range of the Great Auk (Alea impennis) as indicating 
the presence of a former more continuous coastline between the 
British Islands, Iceland, Greenland, and Newfoundland, in all of 
which countries this bird was known to have been abundant.® Yet, 
after all, the best evidence in favour of a North Atlantic land-bridge 
is furnished by the invertebrates. Our special attention is drawn by 
Mr. Born to the importance of the ‘Running Beetles’ of the genus 
Carabus. From the fact of their being wingless and usually found 
under stones or clods of earth, they are not liable to be transported 
accidentally by any of the means usually supposed to aid animals in 
their dispersal. Mr. Born claims that at least two European species 
of Carabus, viz. C. catenulatus and C. nemoralis, have crossed the 
Atlantic by means of an ancient land-bridge. A third form— Carabus 
groenlandicus Chamissonis—seems to have originated in America, and 
to have travelled from there to Greenland and Lapland.* 
Of another group of insects—the Collembola—Professor Carpenter 
remarks: ‘(It is of interest to find that the presence of not a few 
species of these wingless insects in America, in Greenland, in the 
islands to the north of Europe and Asia, and on the Euro-Asiatic 
continent, lends support to our belief in a Pliocene or Pleistocene 
1 A. T. Drummond, ‘‘ Plants common to Europe and America’’: Natwre, 1904, 
Ixx, 55. 
oh Hanitsch, ‘‘ Freshwater Sponges of Iveland’’: Zrish Nat., 1895, iv, p. 126. 
Aer endate, “© Freshwater Sponges in Scotland’? : Journ. Linn. Soc. (Zool.), 
1908, xxx. 
3B. FB, Scharff, Luropean Animals, 1907, pp. 37-9. 
4 Paul Born, ‘‘Carabologische Studien”: Entomol. Wochenblatt, 1908, xxv, 
PD: oye 
