Fauna and Flora of New Zealand. 443 
marine fishes, a southward extension of the Indo-Pacific fauna 
with a well-marked Antarctic element, the South-American 
element being but slightly developed. The main point of 
interest is the difference exhibited between them and the 
marine Mollusca of temperate Australia and Tasmania, shown 
chiefly in the absence trom our seas of many common sub- 
tropical forms. Tasmania, for example, possesses several 
species of Conus, Cyprea, Fasciolaria, and Oliva, of which 
we have no representatives. We have but one species each 
of the genera Mitra, Columbella, and Nassa; while Tasmania 
has respectively 14, 10, and 5 species. We have only 3 
species of Voluia and 2 of Marginella, while Tasmania has 
7 of the former and 8 of the latter. This great difference is 
probably accounted for by the warm south-east current that 
flows down the coast of Australia, and the cold south-west 
current that sweeps the shores of New Zealand. If, however, 
New Zealand was joined to Northern Australia or New 
Guinea all this would be changed; the warm current would 
pass down its east coast, while the cold current would be 
deflected from the west coast of New Zealand to the east coast 
of Australia. But the difference in the shells was nearly as 
well marked in Tertiary times as now; consequently we must 
suppose that New Zealand has been isolated, and that the 
warm current has passed down the east coast of Australia 
ever since these genera inhabited the districts. Now Voluta, 
Mitra, Conus, Fasciolaria, and Cyprea date from the Upper 
Cretaceous, the others from the Eocene, and the conclusion 
seems plain that New Zealand has not been connected with 
Australia since the Cretaceous period, which agrees well with 
the inference derived from the fragmentary nature of our 
avifauna. 
The geographical relations of our insects and spiders are not 
yet known, but as the families of insects in many cases date 
back to the Jurassic, and several genera to the Cretaceous 
period, we may expect to find a marked South-American 
element among them; indeed, Mr. Meyrick has, in papers 
read to our society, already pointed out that in the Crambidee 
the New-Zealand species of Diptychophora are more closely 
related to South-American than to the single Australian 
species; and that among the Geometrina the genera Azelina, 
Drepanodes, and Siculoides are South American, while Tato- 
soma is found in Europe, Ceylon, Borneo, Australia, and 
South America, the New-Zealand species being nearest to 
those of South America. Peripatus is no doubt a very old 
form; it is found in South Africa, Chili, Central America, 
and the West Indies, and consequently cannot be considered 
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