4 INTRODUCTION. By Dr. A. .Seit/. 



and Indo - Chinese butterflies , which result in the appearance of a single species , on aU those larger and 

 smaller islands of the Malaj^ Archipelago, in a dress similar, j'et with constant differences according to the 

 locality. But since the species of the Old World have been split up into such a large number of races or 

 local varieties, or subspecies, rainy- and dry-season forms, mountain forms and those of the lowlands, the 

 more compact South America, being for the most part more regulai-ly tempered, without pronounced rainj' 

 season, has lost very much of its preeramence. 



Now when one takes into consideration that any butterfly, of whatever species, would be able to 

 tl}' from Canada as far as to Cape Horn without meeting with any direct, insurmountable obstacle — neither 

 such a sharplj^ defined desert as separates Northern from Central and Southern Africa, nor a sea, as between 

 Australia and India — it is not easy to understand how it is that we find Castnias, Neotropids, Hesperids 

 or Catagrammas in almost every district of America in distinct forms, mostly unconnected with one another 

 by transitions. In this is manifest a creative energy of unusual richness, such as occurs in no other 

 country to the same extent. 



The lavish endowment of its species with brilliant and conspicuous colours is the second principal 

 characteristic of the American fauna. In India and tropical Africa there are also plent}' of gaj^ species, 

 which fact we do not leave out of account; but while the Old World ever3rwhere produces, side by side 

 mth the gay and riclily ornamented forms, multitudes of others which are tawny, white or neutral brown 

 in colour, manj;' of the open places in the South American woods are alive with the httle gold- and silver- 

 marked Syntomids or the azure blue giant butterflies. None of the Old World species can vie with 

 Argopteron aiireipemih in its pure golden under surface, or show such rich adornment of silver as Bione 

 moneta, or such briUiant blue ground colour as MorpJw cijpris. And even those colours which have not the 

 metallic or silky gloss are nevertheless extremely elegant and pleasing in their arrangement. Very frequentljr 

 they consist of bright red, orange or blue-green bands or longitudinal spots on a deep black ground, 

 resulting in more quiet richness and fulness of colour than a stiffer, more overloaded scheme of markings. 

 Such crude contrasts of colour as occur in the Papilio agamemnon group, in Neurosigma and in Catphisus, 

 are rare in America. A deeply coloured , though almost always onlj^ luiicolorous band suffices to make 

 Epicalia, Clilorippe and Prepona, CaUicore and Adelpha the most beautiful forms which a refined taste 

 could imagine. 



The phenomenon of raimicrj^ which was full}' discussed in the introduction to the first part of this 

 work, appears in America in an altogether special and characteristically modified manner. There are many 

 localities in South America, often quite circumscribed in extent, in which almost all the lepidoj^terous species 

 that occur in any numbers have one and the same wing-pattern indifferently, whether they be butterflies 

 or moths, whether stoutly-built Swallowtails or weak Pierids or shy Nymphalids. In Colombia one may 

 see flying about a single flowering shrub a number of butterflies all coloured and marked ahke, but 

 belonging to four entirely different groups. They are all black with an obhque scarlet band on the 

 forewings. The first is a Piei'id (Pereitte leucodrosijme), the second a Heliconius (Heliconms melpomene), the 

 third a Swallowtail (Papilio eutopiuns) and the fourth (Adelplia isis) a species of Nymphalid allied to 

 LimeuHis. In certain districts of Southern Brazil a yellow band on the forewing and dentated longitudinal 

 stripes on a brownish j-ellow ground provide the general scheme, which is followed by Pierids (Perhyhris, 

 DismorpJiid), Danaids (Lijcorea), Heliconians (Heliconius narcaea) and even some moths (Chetone). I have 

 elsewhere spoken of a tendency of certain districts to produce uniformity in their inhabitants, and 

 although kindred phenomena are not wanting in India, or particularly in Africa, they are far less 

 conspicuous there than in America. 



Just as the present mammalian fauna of South America is wanting in gigantic forms, so too its 

 Lepidoptera are for the most part of only medium size. Onlj' in CaUgo, Motpho, some Sphingids and the 

 giant Noctuid Thysania agrippina do we find great dimensions attained; there are no actual parallels to the 

 huge Atfacus, or to Ornithoptera with its great uncouth females. And as in size, so also in shape there is 

 not the same tendency towards grotesque, unintelligible forms as one is struck by in many 

 genera of the Old World, such as Lepfocircus, Sericinus, Drurya antimacluis , etc. Be5^ond the dcA'elopment 

 of tails in normallj- untailed families (Nyinpludidae, Erycinidac, Hesperidae) there is little that is very strange 

 in the aspect of the American Lepidoptera, 



In addition to these peculiai'ities of the American fauna, there are some others which are not so 

 difficult to explain. In a large number of districts, especially in South America, there are no regular wet 

 and dry seasons. In the neighbourhood of Rio de Janeiro sudden changes are possible on almost any day 

 of the J'ear, and the rainless periods are variable both in their duration and in the time of their arrival. 

 Thus the conditions there — as we have akeady briefly mentioned — do not lend themselves in tire same 

 pronounced wa\- to the development of seasonal dimorphism as in many localities of the Old World, where 

 the conditions of weather are perfectly regular, the rains and the heat of the sun being confined to certain months. 



Polymorphism also does not seem , in another respect , to be developed to the same degree as in 

 the Old World; namely, in its local conditions. Although in Papilio hjsithous, for example, we observe the 

 same conditions which obtain m many Indian species, namelj' that in different districts it mimics the different 



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