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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,' so that it is impossible to attribute the fact to other than some local influence. In Celebes, as I have elsewhere pointed out,? 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.
Iu 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 Euplaa is tlie 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.
From the Fiji Islands we have comparatively few butterflies; 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 Euplea' not closely related, and all of more intense metallic lustre than their allies in other islands.
i Ornithoptera priamus, 0. helena, Papilio deiphobus, P. ulysscs, P. gambrisius, P. codrus, Iphias leucippe, Euploca prothoë, llestia idea, Athyma jocuste, Dilema pandarus, lymphalis pyrrhus, V. euryalus, Drusilla juirus.
3 “Contributions to the Theory of Natural Selection," pp. 168-173.
• These insects are described and figured in the " Procecdings of the Zoological Society," for 1877, p. 139. Their names are Euplera browni, Alcides aurora, and Batocera broreni. • Euplaa herritsonii, E, diocletiana, E. lotifica,
flere also we have one of the large yellow Ornithopteræ (0. magellanus), whose hind wings glow with an intense opaline lustre not found in any other species of the entire group; and an Adolias' 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 metallic colouring surpass anything found in the whole eastern hemisphere, if not in the whole world.
In the Andaman Islands in the Bay of Bengal there are a considerable number of peculiar species of butterflies differing slightly from those on the continent, and generally in the direction of paler or more conspicuous colouring. Thus two species of Papilio which on the continent have the tails black, in their Andaman representatives have them either red or white-tipped.? Another species: is richly blue-banded where its allies are black; while three species of distinct genera of Nymphalidæ* all differ from their allies on the continent in being of excessively pale colours as well as of somewhat larger size.
In Madagascar we have the very large and singularly white-spotted Papilio antenor; while species of three other genera’ are very white or conspicuous as compared with their continental allies.
Passing to the West-Indian Islands and Central America (which latter country has formed a group of
• Papilio rho.lifer (near P. doublulayı), and Papilio charicles (near P. memnon).
s Pupilio mayo. • Euploa amamonensis, Crthosia biblis, Cyreslis cocles. s punais nossima, Alelunitio massoura, Diudema dezithea.
islands in very recent times) we have similar indications. One of the largest of the Papilios inhabits Jamaica,' while another, the largest of its group, is found in Mexico. Cuba has two of the same genus whose colours are of surpassing brilliancy;: while the fine genus Clothilda-confined to the Antilles and Central America — is remarkable for its rich and showy colouring.
Persons who are not acquainted with the important structural differences that distinguish these various genera of butterflies can hardly realize the importance and the significance of such facts as I have now detailed. It may be well, therefore, to illustrate them by supposing parallel cases to occur among the Vammalia. We might have, for example, in Africa, the gnus, the clands, and the buffaloes, all coloured and marked like zebras, stripe for stripe over the whole body exactly corresponding. So the hares, marmots, and squirrels of Europe might be all red with black feet, while the corresponding species of Central Asia were all yellow with black heads. In North America we might have raccoons, squirrels, and opossums, in particoloured livery of white and black, so as exactly to resemble the skunk of the same country; while in South America they might be black with a yellow throat-patch, so as to resemble with equal closeness the tayra of the Brazilian forests. Were such resemblances to occur in anything like the number and with the wonderful accuracy of imitation met with among the Lepidoptera, they would certainly attract universal attention among naturalists, and would lead to the exhaustive
· Papilio homerus. : P. daunus. ' P. gundlachianus, P. rilliersi,
study of the influence of local causes in producing such startling results.
Onc somewhat similar case docs indeed occur among the Mammalia, two singular African animals, the Aardwolf (Proteles) and the hyæna-dog (Lycaon), both strikingly resembling hyænas in their general form as well as in their spotted markings. Belonging as they all do to the Carnivora, though to three distinct families, it seems quite an analogous case to those we have imagined; but as the Aard-wolf and the hyæna-dog are both weak animals compared with the hyæna, the resemblance may be useful, and in that case would come under the head of mimicry. This scens the more proLable because, as a rule, the colours of the Jammalia are protective, and are too little varied to allow of the influence of local causes producing any well-marked effects.
When we come to birds, however, the case is different; for although they do not exhibit such distinct marks of the influence of locality as do butterfliesprobably because the causes which determine colour are in their case more complex-yet there are distinct indications of some effect of the kind, and we must devote some little time to their consideration.
One of the most curious cases is that of the parrots of the West-Indian Islands and Central America, several of which have white heads or foreheads, occurring in two distinct genera,' while none of the more numerous parrots of South America are so coloured. In the small islanil of Dominica we have a very large and richly
Pionus allifrons and Chrysutis senilis (C. America), Chrysotis sallai (Hayti).
coloured parrot (Chrysotis augusta) corresponding to the large and richly-coloured butterfly (Papilio homerus) of Jamaica
The Andaman Islands are equally remarkable, at least six of the peculiar birds differing from their continental allies in being much lighter, and sometimes with a large quantity of pure white in the plumage,' exactly corresponding to what occurs among the butterflies.
In the Philippines this is not so marked a feature ; yet we have here the only known white-breasted kingcrow (Dicrurus wirabilis); the newly discovered Euryla mus steerii, wholly white beneath; three species of Diceum, all white beneath ; several species of Parus, largely white-spotted; while many of the pigeons have light ashy tints. The birds generally, however, have rich dark colours, similar to those which prevail among the butterflies.
Iu Celebes we have a swallow-shrike and a peculiar small crow allied to the jackdaw, whiter than any of their allies in the surrounding islands; but otherwise the colours of the birds call for no special remark.
In Timor and Flores we have white-headed pigeons," and a long-tailed flycatcher almost entirely white.
In Duke-of-York Island cast of New Guinea we find that the four new species figured in the " Proceedings of the Zoological Suciety,” for 1877, are all remarkable for the unusual quantity of white in their plumage. They consist of a flycatcher, a diceum, a wood-swallow, and
i Kittacinclu allirentris, Geocichla alligularis, Seurnia undamanensis, Ilylotirpe grisola var., Ianthanas palumbwiiles, Osmotreron chloroptera.
· Artamus munichus, Corrus adrena.