Hi 
INTRODUCTION. 
the immense antiquity thus given to the group and their universal distribution in past time, renders 
all suggestions of special modes of communication between the parts of the globe in which their 
scattered remnants now happen to exist altogether superfluous and misleading ” *. 
In his last-named work, Mr. Wallace divides all known islands into two classes, “ Continental ” and 
“ Oceanic.” The former are always more varied in their geological formation — containing both ancient 
and recent stratified rocks — are rarely remote from a continent, and always contain some land Mam- 
malia, also Amphibia and representatives of the other classes of animals in considerable variety. The 
“ Oceanic ” islands are usually far removed from continents and are always separated from them by very 
deep seas, are entirely without land Mammalia or Amphibia, but are generally well stocked with birds 
and insects and with some reptiles. Now New Zealand, which is undoubtedly “ Continental ” in its 
geological formation, also in the existence of the submerged bank already described connecting it in 
ancient times with North Australia and New Guinea, is as decidedly “Oceanic” in its zoological 
character, except as regards its wingless birds and the remarkable tuatara lizard ( Sphenodon 
pnnctatum ), which is said to constitute per se a distinct order of Reptilia of extreme antiquity. 
Mr. Wallace therefore terms New Zealand and the Celebes, where the conditions are somewhat 
similar, “Anomalous islands;” but Ancient continental may be perhaps a more convenient term. 
As already explained, at the time of the supposed land-connection to the North-west, the 
Marsupial fauna could not have reached the eastern land now forming part of Australia; but it seems 
very probable that, at this early period, tropical Australia was tenanted by some Struthious kind of bird, 
perhaps volant in its character, which had reached this land, by way of New Guinea, through some 
ancient continental extension. If this theory, so well propounded by Mr. Wallace, is the true one, 
then the Cassowaries of New Guinea, the Emus of Australia, the extinct Dromomis of Queensland, 
and the Moas and Kiwis of New Zealand are doubtless the modified descendants of this ancestral 
type. “ The total absence (or extreme scarcity) of mammals in New Zealand obliges us to place its 
union with North Australia and New Guinea at a very remote epoch. We must either go back to a 
time when Australia itself had not yet received the ancestral forms of its present marsupials and 
monotremes, or we must suppose that the portion of Australia with which New Zealand was con- 
nected was then itself isolated from the mainland, and was thus without a mammalian population. . . 
But we must on any supposition place the union very far back, to account for the total want of 
identity between the winged birds of New Zealand and those peculiar to Australia, and a similar 
want of accordance in the lizards, the freshwater fishes, and the more important insect groups of the 
two countries. From what we know of the long geological duration of the generic types of these 
groups we must certainly go back to the earlier portion of the Tertiary period at least in order that 
there should be such a complete disseverance as exists between the characteristic animals of the two 
countries, and we must further suppose that, since their separation, there has been no subsequent 
union or sufficiently near approach to allow of any important inter-migration, even of winged birds, 
between them. It seems probable, therefore, that the Bampton shoal west of New Caledonia, and 
Lord Howe’s Island further south, formed the western limits of that extensive land in which the 
great wingless birds and other isolated members of the New-Zealand fauna were developed. Whether 
this early land extended eastward to the Chatham Islands and southward to the Macquaries we have 
no means of ascertaining ; but as the intervening sea appears to be not more than 1500 fathoms deep, 
* ‘ Island Life,’ by Alfred Enssel Wallace, pp. 451, 452. 
