to an Insect Fauna of the Amazon Valley. 349 



P. Zagreus, Doubled, and Hewits. Gen. D. L. pi. 1*, f. 1. 



The species has been found ia Venezuela and in New Granada. I obtained one 

 example, at Catii^, near Ega, in November, 1850. The Heliconide which it 

 most lesembles is Lycoreu Atergat'n, Dbld., a species also confined apparently to 

 the same distiicls of country as the Papilio. 



Obs. Having concluded the review of the Amazonian species of 

 Pajiitio, I think it will be useful to employ the results to illustrate 

 further some of the subjects mentioned in the remarks at the com- 

 mencement of the article ; especially the interesting one of the 

 relation of the Amazonian "fauna to those of other countries of 

 tropical America. The species are such conspicuous objects, 

 and are so well represented in collections, that they afford good 

 data for arriving at conclusions, which I think are not likely to be 

 falsified by any subsequent group of which we have to treat. The 

 simplicity and distinctness of the markings and colours also afford 

 good characters by which to measure the amount of modification 

 the species undergo from one locality to another. The Valley of 

 the Amazons, as I said before, has been classed, with regard to its 

 Zoological and Botanical productions, together with Columbia and. 

 Guiana, as forming one great province, the Columbian. On the 

 north this is separated from the Mexican province by the Isthmus 

 of Panama; on the west from the Peruvian by the chain of the 

 Andes ; the great Brazilian province on the south beginning from 

 the southern borders of the alluvial plains of the Amazons. 



The species oP Papilio confirm, what however is a well-esta- 

 blished fact, the distinctness of the Brazilian province; but I 

 think they also afford very strong grounds for considering the 

 Guiiina region (comprised between the Atlantic on the one hand, 

 aad the rivers Orinoco, Negro and Amazons on the other) as a 

 perfectly independent province, possessing a peculiar character in 

 its productions, and having a very large proportion of species pe- 

 culiar to itself. I think it will also appear, that the Valley of the 

 Amazon, from the mouth of the river to about 72° W. long, 

 (where Columbian begin to predominate over Guiana forms), has 

 received its fauna chiefly from this region. Of about fifty species 

 and distinct local sub-species of Papilio found in the two districts 

 of Guiana and Amazonia, I find that no less than twenty-nine are 

 found in no other country. It is true that a large proportion of 

 species, as far as we are at present aware, seem peculiar to Ama- 

 zonia ; but these are nearly all very closely related to, and some 

 of them evidently local forms or modifications of, Guiana species. 

 In comparing the Amazonian fauna with that of Guiana, it must be 



