460 ZOOLOGICAL GEOGRAPHY. [pabt hi. 



an outline sketch of the main features of the New Zealand 

 fauna and of its relations with other regions, we may consider 

 what conclusions are fairly deducible from the facts. As the 

 outlying Norfolk, Chatham, and Lord Howe's Islands, are all 

 inhabited (or have recently been so) by birds of New Zealand 

 type or even identical species, almost incapable of flight, we may 

 infer that these islands show us the former minimum extent of the 

 land-area in which the peculiar forms which characterise the 

 sub-region were developed. If we include the Auckland and 

 Macquarie Islands to the south, we shall have a territory of not 

 much less extent than Australia, and separated from it by per- 

 haps several hundred miles of ocean. Some such ancient land 

 must have existed to allow of the development and specialization 

 of so many peculiar forms of birds, and it probably remained 

 with but slight modifications for a considerable geological period. 

 During all this time it would interchange many of its forms of 

 life with Australia, and there would arise that amount of identity 

 of genera between the two countries which we find to exist. Its 

 extension southwards, perhaps considerably beyond the Mac- 

 quaries, would bring it within the range of floating ice during 

 colder epochs, and within easy reach of the antarctic continent 

 during the warm periods ; and thus would arise that interchange 

 of genera and species with South America, which forms one of 

 the characteristic features of the natural history of New Zealand. 

 Captain F. W. Hutton (to whose interesting paper on the 

 Geographical relations of the New Zealand Fauna we are 

 indebted for some of our facts) insists upon the necessity of 

 former land-connections in various directions, and especially 

 of an early southern continental period, when New Zealand, 

 Australia, Southern Africa, and South America, were united. 

 Thus he would account for the existence of Struthious birds 

 in all these countries, and for the various other groups of 

 birds, reptiles, fishes, or insects which have no obvious means 

 of traversing the ocean, — and this union must have occurred 

 before mammalia existed in any of these countries. But 

 such a supposition is quite unnecessary, if we consider that 

 all wingless land-birds and some water-birds (as the Gare-fowl 



