Page:Transactions NZ Institute Volume 15.djvu/60

that out of about 650 European Tortricina only about a dozen, or two per cent. possess this structure; though in Australia the proportion is sixteen per cent. and in New Zealand thirty-six per cent.

The New Zealand Tortricina are of a very fragmentary sort; even those that are congeneric are very rarely at all closely allied specifically. The fauna certainly strikes one as not having been developed on the spot from a few types, but as being the broken remains of a much more extensive one; though it might possibly have been derived by scanty immigration from different sides. Unfortunately there is practically little or nothing known of the South American Tortricina, nor of those of the South Pacific Islands. The affinity with Australia is, however, clear.

The Tortricidæ are represented by 11 genera; of these 4 are cosmopolitan, 4 Australian, and 3 (so far as known) endemic. Of the cosmopolitan genera, the single species of Capua, and three species of Tortrix, are closely allied to Australian forms. Two, however, of the endemic genera, viz., Prothelymna and Eurythecta, are widely remote from any known Australian genera. The entire absence of Teras and Sciaphila, a marked characteristic of Australia, is here equally noticeable. Eight genera of Grapholithidæ occur; but of these, two are not indigenous; and a third, Strepsiceros, is represented only by two species, which both also occur in Australia, being the only two Tortricina apparently native to both countries. As this genus is considerably developed in Australia, of which it is peculiarily characteristic, and as there are no known species peculiar to New Zealand, I am disposed to think that both of these must have been in some way artificially introduced.^[1] Of the remaining five genera, four are isolated and endemic, containing each a single species, three of them having some apparent affinity with Strepsiceros; the fifth, Pædisca, is the solitary representative of the large group of genera closely allied to Grapholitha, dominant in Europe and North America, but absent from Australia, so that this species is locally quite isolated. The Conchylidæ are represented by only one genus, found also in Australia, and of a group characteristically Australian; there are structural reasons for supposing this genus to be one of the oldest types of its family. On the whole, therefore, it will be seen that the fauna is distinctly Australian in character, with some few curious and at present inexplicable exceptions.