122 MOSTLY MAMMALS 
But the evidence for a land connection by way of the 
Pacific does not by any means rest on the testimony of 
marsupials and tortoises alone. Passing over certain 
groups, it may be mentioned that the earthworms of 
Australia and New Zealand are strangely like those of 
Patagonia, and have no very near relatives in Africa; 
while an almost equally strong affinity is stated to exist 
between the Patagonian and Polynesian land-slugs. Neither 
of these groups of animals are fitted to withstand the cold 
of high latitudes, and it is difficult to see how the members 
of the second, at any rate, could have reached the two 
areas by any other means than a direct land connection. 
Turning to the reports of the Funafuti boring, it appears 
that this has been carried far below the limits of coral 
life, and was still in coral limestone. So far, therefore, 
the advocates of the theory that Polynesia is the remains 
of a sunken continent have scored a great triumph; and 
although there is still the possibility that some of the 
atolls in this vast area may prove to be perched on the 
denuded summits of extinct submarine volcanoes, even 
this would not interfere with the general conclusion. If 
deeper borings should result in touching rocks more or 
less similar to ordinary continental sedimentary deposits 
or metamorphic crystallines, an even firmer basis would 
be afforded to the hypothesis of subsidence which has 
now received such striking confirmation. 
As the result of the boring, it appears, then, that there 
is a possibility that the community between the South 
American and Australasian faunas may admit of being 
explained by means of a direct land connection between 
the two areas at a comparatively recent geological date. 
Even, however, if this explanation receive future support 
and acceptation, there are, as in all similar cases, still 
