v COLOURS OF ANIMALS 385 



Equally remarkable is the increase of size in some islands. 

 The small island of Amboina produces larger butterflies than 

 any of the much larger islands which surround it. This is 

 the case with at least a dozen butterflies belonging to many 

 distinct genera, 1 so that it is impossible to attribute the fact 

 to other than some local influence. In Celebes, as I have 

 elsewhere pointed out, 2 we have a peculiar form of wing and 

 much larger size running through a whole series of distinct 

 butterflies ; and this seems to take the place of any speciality 

 in colour. 



In a very small collection of insects recently brought from 

 Duke-of-York island (situated between New Britain and New 

 Ireland) are several of remarkably white or pale coloration. 

 A species of Euplsea is the whitest of all known species of 

 that extensive genus ; while a beautiful diurnal moth is much 

 whiter than its ally in the larger island of New Guinea. 

 There is also a magnificent longicorn beetle almost entirely 

 of an ashy white colour. 3 



From the Fiji islands we have comparatively few butter- 

 flies ; but there are several species of Diadema of unusually 

 pale colours, some almost white. 



The Philippine islands seem to have the peculiarity of 

 developing metallic colours. We find there at least three 

 species of Euplsea 4 not closely related, and all of more 

 intense metallic lustre than their allies in other islands. 

 Here also we have one of the large yellow Ornithopterse 

 (0. magellanus), whose hind wings glow with an intense 

 opaline lustre not found in any other species of the entire 

 group; and an Adolias 5 is larger and of more brilliant 

 metallic colouring than any other species in the archipelago. 

 In these islands also we find the extensive and wonderful 

 genus of weevils (Pachyrhynchus), which in their brilliant 



1 Ornithoptera priamus, 0. Helena, Papilio deiphobus, P. ulysses, P. gam- 

 brisius, P. codrus, Iphias leucippe, Euplaea prothoe, Hestia idea, Athyma 

 jocaste, Diadema pandarus, Nymphalis pyrrhus, N. euryalus, Brasilia jairus. 



3 Contributions to the Theory of Natural Selection, pp. 168-173. 



3 These insects are described and figured in the Proceedings of the Zoolo- 

 gical Society for 1877, p. 139. Their names are Euplsea browni, Alcides 

 aurora, and Batocera browni. 



4 Euplsea hewitsonii, E. diocletiana, E. Isetifica. 

 6 Adolias calliphorus. 



2c 



