332 RHOPALOCERA MALAYAN A. 



furuiture maker that he had l)eeu offered a large quantity at a low rate for the decoration of 



Subgenus PAPILIO. 



The princii^al diagnostic characters of Papilio have already been given (antca, p. 324), and 

 the characters by which Oniithoptcra differs in a subgeneric sense have also been described 

 {aiiti'tt, p. 325), so that it only remains to give the structural characters of the groups into 

 which Papilio is divided. 



One great feature in Papilio is the extraordinary diversity of coloration found among its 

 species. Even in this fauna we have melanic types, like P. pammoii, P. iswara, and others, 

 whilst in P. aniiphates we have a totally dissimilar and paler coloration. The whole question 

 as to the coloration of insects is still extremely obscure, though a new theory is sometimes 

 advanced. f 



In the tropics the Papilios form no inconsiderable portion of the principal feature of 

 butterfly existence. Dr. Hooker vividly describes their abundance and appearance near 

 Darjeeling. " They were seen everywhere, sailing majestically through the still hot air, or 

 fluttering from one scorching rock to another, and especially loving to settle on the damp sand 

 of tlie river-edge ; where they set by thousands, with erect wings, balancing themselves with 

 a rocky motion, as their heavy sails inclined themselves to one side or the other ; resembling a 

 crowded fleet of yachts on a calm day. Such an entomological display cannot be surpassed." :J 

 In Angola, Mr. Mouteiro found the finest Papilios, in contrast to the shade-loving habits of 

 some other genera, "only in the full sunshine, on the low bushes and flowering plants, 

 skirting, as with a broad belt, the woods or forest." § On the contrary, however, Mr. Bates, 

 when in South America, and in the rich rhopalocerous region of Para, found " those species 

 of Papilio which are most characteristic of the country, so conspicuous in their velvety-black, 

 green, and rose-coloured hues never leave the shades of the forest." || Doubleday 



''• It is surprising how many livinf» creatures are abnost exterminated by man for his gratification in ornamentation, or to 

 satisfy his utilitarian propensities. Quite recently, in this country tlie robin was slaughtered to provide a head-ih-ess for ladies, 

 aiiil at the present time the hats and bonnets of our female fiieuds are frecpiently decorated with the skin of some tropical bird. 

 At the Norfolk Broads the angler catches the bream for sport, and often consigns them to the cottager to manure his garden ; 

 whilst at Skomer Island, we have recently leamt from the Be\'. M. A. Mathew. that midtitudes of shearwaters are " destroyed 

 by the farm servants, and the bothes of the birds ploughed into the gi'ouud as a dressing for wheat " (' Zoologist,' ser. 3, vol. viii. 

 p. 48.5). Even man does not spare his fellow in this civilizing process, as in the time of the gi-eat French Re\olntion, when, 

 as Carlyle teUs us, the hair of the guillotined was used for the manufacture of •• jierruques blondes" and quotes Montgaillard 

 that at Meudon " there was a tannery of human skins ; siich of the guillotined as seemed worth flaying ; of which perfectly good 

 wash-leather was made." 



f One of the most important suggestions on this subject has recently been formulated by Lord Walsinghani ("On some 

 probable causes of a tendency to melanic variation in Lepidoptera in high latitudes," the annual Presidential Address to tlie 

 Yorkshire Naturalists' Union, Doncaster, March 3, 1885). In discussing the probable explanation of tlie white co-i'ering of 

 many Arctic and Alpine mammals and birds, and the dark hue of many lepidopteral species in the same habitats, he has 

 accepted the views set forth at least by Craven in 1846, as explanatory of the first phenomenon, which accounts for the same by 

 the well-known fact of white being a bad radiator of solar energy, and white-covered animals thus being able to retam their heat 

 to the greatest adAantage. The dark insects, on the contrary, are considered to have their advantage in being better able to 

 absorb the solar radiation. Mr. Meldola has well summarised these views hi the following words: — " In the case cpf wariu- 

 bliioded animals the loss of heat by radiation is retarded by the white covering, whilst in insects, which develop but little heat 

 by res])iration, it is of the utmost importance to utilize as much as possible of the solar energy" ('Nature,' vol. xxxi. p. 505). 

 A)i ex<'plleiit resume of Lord Walsingham's theory has been given by Mr. J. Jeiiner Weir (' Entomologist,' vol. xviii. p. 81). 



This theory throws little light, however, on the coloration of tropical butterflies, a question still requiring suggestions 

 for a solution. 



' 'Himalayan .Journals,' vol. i. p. 143, § 'Angola,' vol. i. p. 171. 



\\ ' The Naturalist on the Ania/.ous,' ord edit. p. 5'2. 



