MEETINGS OF SOCIETIES. 83 
countries since the period when mammalia had peopled all the 
great continents. 
Last year the issue of Mr. Wallace’s most interesting work 
on “ Island Life” added another contribution to our knowledge 
of the question under discussion, and the three chapters devoted 
to New Zealand put the problems very clearly before us. <A very 
important factor, and one which had not hitherto been considered, 
is now introduced, viz., the relative depths of the seas sur- 
rounding Australia and New Zealand. It is shown, by the aid of 
a map, that if the whole of the circumjacent ocean, which is at 
present less than 1000 fathoms in depth, was to be elevated above 
sea-level, a very remarkable change in the conformation of the 
existing land would take place. New Zealand would be extended 
very greatly to the west and north-west, and two long narrow 
arms would stretch, one to Lord Howe’s Island, and the other by 
Norfolk Island to the Great Barrier Reef, and thus a connection 
with North-eastern Australia would be made. The same eleva- 
tion would extend the area of Australia, round its western, 
southern, and eastern coasts, while a long tongue of land would 
unite it with Tasrnania, and would reach to the soth parallel S. 
latitude. But even with this great elevation of 6o000ft., a wide sea 
would remain between New Zealand and temperate Australia. 
The northern extension of Australia would connect it on the one 
hand with Malaysia, Borneo, and Celebes, while from New Guinea 
a broad eastern extension would include the New Hebrides. 
Starting from these indications, Mr. Wallace shows that we ought 
to expect to find that New Zealand was most probably connected 
at a remote period “ with tropical Australia and New Guinea, and 
perhaps, at a still more remote epoch, with the great southern 
continent, by means of intervening lands and islands,” as ‘“‘a sub 
marine plateau ata depth somewhere between one and twothousand 
fathoms stretches southward to the antarctic continent.” 
It is not my intention here to follow Mr. Wallace in all the 
arguments he adduces to show the origin of our fauna, but a few 
of his facts are suggestive and confirmatory of his theory, as 
opposed to that of Prof. Hutton’s, which he again discusses at 
some length. Thus our struthious birds are shown to be allied, 
not to the rheas of South America, but to the cassowaries and 
emus of North Australia and New Guinea. Again, “ the starling 
family, to which four of the most remarkable New Zealand birds 
belong (the genera Cveadion, Heterolocha, and Calleas) is totally 
wanting in temperate Australia, and is comparatively scarce in 
the entire Australian region, but is abundant in the Oriental 
region, with which New Guinea and the Moluccas are in easy 
communication. It is certainly a most suggestive fact that there 
are more than sixty genera of birds peculiar to the Australian 
continent (with Tasmania), many of them almost or quite confined 
to its temperate portions, and that no single one of these should 
be represented in temperate New Zealand.” 
But this connection with tropical Australia must necessarily 
have been at a remote period, before the latter received its 
mammalian fauna, or else that portion of Australia which was in 
connection with New Zealand “ was itself isolated from the main 
land, and was thus without a mammalian population.” And this 
is the essentially novel and interesting part of the theory, which 
