68 INSECTS OF SAMOA. 



is much diversity of larval habits, but probably a considerable proportion of 

 the genera feed on mosses, lichens, dead wood and bark, which would be avail- 

 able anywhere, whilst even the more highly developed genera, which are attached 

 to plants of special character, are not in general more exacting than other leaf- 

 feeders (such for example as the Gracilariad Acrocercops, which is indigenous 

 in all three regions). Nevertheless, not a single species of Oecophoridae has 

 occurred in Samoa ; neither has a single one been found in Hawaii, though the 

 fauna of that group is now very well known and has some remarkable analogies 

 with that of New Zealand, such as the excessive development of the Pyralid 

 genus Scoparia, found everywhere in New Zealand associated with Oecophoridae 

 and probably often feeding on the same plants, yet in Hawaii unaccompanied. 

 Hawaii can only have obtained its fauna by wind transportation over a wide 

 sea, and some of its eccentricities may reasonably be attributed to chance ; but 

 a striking feature like this, shared by Hawaii and Samoa, cannot be accidental ; 

 there must be some compelling cause, though at present I am unable to suggest 

 its nature. A single Oecophorid only has been taken in Fiji, a species of the 

 Australian genus Peritorneuta. 



The larvae referred to as refuse-feeders live on a great variety of dead or 

 decaying vegetable matter, such as the dead stems, leaves, or seed-vessels of 

 sugar-cane, cotton, coconut, etc., also apparently on the excrement or rubbish 

 left by other insects in such situations, thus acting as scavengers ; this habit 

 of life is less usual in cool or dry countries, but seems especially favoured in 

 hot damp climates, where such materials are naturally more liable to disintegra- 

 tion. Larvae with these habits must always have had a good chance of being 

 transferred from one island to another by the natives in their canoes, ever since 

 the earliest appearance of man in the region. It must not be assumed that such 

 insects are not injurious ; it is found in some cases that when plentiful, their 

 natural food running short, they may gnaw the substance of the growing plants,, 

 and damage the buds or vegetating shoots. 



Pterophoeidae 



1. Spenarches caffer Zell. 



Upolu, Apia, March, May ; 2 ex. Also one in Bishop Museum. Occurs 

 in Africa, Seychelles, Ceylon, India to Japan, the Malayan region, New Guinea, 

 Australia, New Hebrides, Tonga, West Indies. Larva very polyphagous, but 



