OF THE AMAZON VALLEY. 557 



10. Heliconius Erato, Linnseus. 

 Papilio Erato, Linn. Mus. Lud. Ulr. 231 (1764). 



Amathusia, Cram. Pap. Exot. t. 177- f- F. (1770). 



Doris, Linn. Mant. 536 (17/1), var. 



, Cram. Pap. Exot. t. 33?. f. C. (1782). 



Quirim, Cram. I. c. t. 65. f. A, B. (1779). 



The two forms, Urato and Doris, offer a striking contrast in their colours, one heing red, 

 the other blue, and were naturally considered two perfectly distinct species. I thought 

 they were such myself, until I bred them from precisely similar larvae, which fed together 

 in one cluster on the same tree. There are males and females in about equal numbers of 

 both forms. I did not find, in the many hundreds of examples which I examiaed, any 

 intermediate variety ; the species, therefore, offers a case of dimorphism of which it is 

 difficult to surmise the purpose. This case of variation in colour may, however, help to 

 explaui how the very diversified species of this genus have originated. H. Ih^ato exists 

 in both forms throughout the delta region of the Amazons, Guiana, and New Granada ; 

 but on the Upper Amazons, at St. Paulo, I found one of them absent, the blue one 

 {Doris) only existing there ; it occurred, however, in great numbers. 



The larva has a series of moderately long hispid spines on each segment of the body : 

 the head is bifid ; in colour it is yellow, with narrow black bands. The chrysalis is smooth, 

 without angles ; the head, however, is prolonged to a point. It is suspended freely by 

 the tail. The pupa-state lasts eight days. 



11. Heliconius Metharme, Erichson. 



Heliconia Metharme, Erichson in Schomburgk's Reise in Brit. Guiana, p. 595. 



This species has very much the appearance of H. Erato (var. Doris), but it wants the 

 patch of blue at the base of the hind wings above ; it has, on the other hand, a series of 

 short bluish lines near the hind margin, which are absent in H. Erato. It was rather 

 a common insect at Ega and St. Paulo, but did not occur at all on the Lower Amazons. 

 The species is found only in the interior of the forest, flying slowly, and delighting to 

 settle on the scarlet blossoms of a climbing-plant ; whilst H. Erato is seen only on the 

 skirts of the woods and in damp waste places. 



12. Heliconitts Melpomene, Linnseus. 

 Papilio Melpomene, Linn. Syst. Nat. ii. 758. n. 71. 

 — , Cramer, Pap. Exot. t. 191. f. C. 



Pound only in the middle part of the Lower Amazon region, at Obydos and Santarem, 

 where the dry, hiUy country of Guiana from the north, and that of interior Brazil from 

 the south, reach the banks of the river. The soil in this part of the banks of the Ama- 

 zons is light and sandy ; the dry and wet seasons are more strongly contrasted, and the 

 forests thinner, than in the rest of the river valley. The species also occurs throughout 

 Guiana, Venezuela, and in New Granada. It is quite absent, however, from the humid 

 forests of the Amazons, both to the east and to the west of the places above mentioned. 



