336 PROCEEDINGS OF SECTION D. 
the ancestral forms to have been more or less cosmopolitan, 
or, at any rate, distributed in a band round the earth, north 
of the Equator, whence they were driven southwards into 
each of the chief continents—driven down either by climatic 
or physical changes, and as a result of competition with the 
more northern, more modern, and more sturdy Lumbricide 
of the Palearctic region. But if this were the case, surely 
it is a most astonishing fact that the same genera, regarded 
as archaic anatomically, with very closely allied species, per- 
sist in the extreme southern ends of the land-tracts. It 
seams strange, indeed, that during their journey from north 
to south, in spite of the struggle for existence with physical 
and organic nature, varying in each of the continents. as 
it must have done, the same genera should persist in Pata- 
gonia, Cape Colony, and New Zealand, while, except on the 
American continent, not a single representative should have 
survived the struggle north of the Equator, across which 
they must have been driven. 
Again, on this supposition, how can we explain the 
absence of species of Notiodrilus on such islands as St. 
Helena, and other long-isolated islands in the different 
oceans, together with the presence on such Antarctic islands 
as have been visited and explored of closely-allied species ; 
identical species on Kerguelen and Marion, closely allied 
to which are other species in South Georgia, Fuegia, Auck- 
land Islands, and Macquarie Island. These last facts seem 
to me to form a very convincing piece of evidence in favour 
of Antarctica; and it is even suggestive of an Antarctic 
origin of the genus. - Blandford says:—‘“ It is highly pro- 
bable that many forms of terrestrial life originated in the 
Southern Hemisphere, and . . . it is far from improb- 
able that the Antarctic continent was an original area of 
development.” 
Again, Lydekker, in his book on geoSraphical distribution 
of mammals, writes: —-‘‘ The Spheniscide (penguins), which 
present a relation to other birds, somewhat analogous to that 
exhibited by Edentates to other mammals, having no ap- 
parent affinity with the group, may prove an exception to 
the rule of northern origin of most of the axisting types of 
terrestrial vertebrates, sincé they are quite unknown in the 
north, and occur fossil both in New Zealand and in Pata- 
gonia.””’ But, however this may be, whether the Acantho- 
drilids, evolving, as they probably did from fresh-water 
Oligochceeta, originated in Antarctica, or in Archiplata, of 
Von Jhering (7.e., Chili and Patagonia), or in Antipodea of 
Forbes—as I think more prabable—they must have spread 
