group of Butterfiies, Potato District, British Guiana. 425 



The solitary specimen with three red markings has them 

 well developed. The specimen is a $, and has the more 

 usual rounded black area to the hind-wing, and it was 

 captured on July 19th, 1904 — the height of the rainy 

 season. 



Heliconius silvana, — The four specimens of this species 

 are of remarkable interest. Two of them bear the usual 

 pattern of black marking on the hind-wing while two 

 show the black area divided by the ground colour, one 

 being a good intermediate. Not one of the four have the 

 white marginal spots developed. The species undoubtedly 

 shows the strong local influence of its relatives, and 

 especially is this to be noted in the two specimens with 

 a banded hind-wing, these conforming with the predomi- 

 nant forms of Mclinxa mneme and Heliconius numata. 

 These banded H. silvana, although rare, have been re- 

 corded elsoAvhere. There are two such specimens in the 

 Hevvitson collection at South Kensington. One labelled 

 Upper Amazon, and another a much smaller specimen, 

 but more completely banded, from Para. The species is 

 evidently on one of the limits of its distribution or would 

 surely be commoner, especially as elsewhere, such as at 

 Para, it is a very common and plentiful insect. 



Heliconius euco7na. — A single specimen was secured by 

 Mr. C. B. Roberts in 1902. it differs in no way from the 

 type, and is a mere accidental visitor, apparently to the 

 Potaro region. The home of the species is on the Lower 

 Amazon. The species readily fits in with the group 

 through the more extremely banded forms of Heliconius 

 7iuviata. 



HeliconIn^, Genus Eueides. 



Three species of Eueides have occurred, Eueides isahella, 

 Eueides vibilia, and Eueides nigrofidva.'^ The two former 

 only singly and the last not uncommonly. It is curious 

 that one of the single specimens (that of E. Isabella) is a 

 common species, while the only species that has occurred 

 at all frequently was found to be an undescribed species. 

 It is this new species that conforms to a considerable 

 extent to the main group, while E. isabella (as far as can 

 be ascertained from a single individual) is of the ordinary 



* Vide Ent. 1906, p. 52. Three other species of Eueides have 

 occurred belonging to another small family group, E. lyhia, E. 

 aliphera, and E. unifasciatus (?). 



