554 MR. H. W. BATES ON THE HELICONIDE LEPIDOPTERA 



3. The black central stripe of tlie hind wing runs from the midcQe of the abdominal 

 edge to the apex of the wing. 



4. The pale submarginal spots of the upper surface are wanting. 



It is curious that these points of diflFerence between S. Numata and S. Sylvana are 

 almost precisely the same as those which distinguish Melincsa Mneme from M. Egina. 

 I judge from this that a mimetic resemblance is intended between the Selieonii and 

 the MelincecB — S. Numata and M. Mneme, H. Sijlvana and M. Egina, — the Heliconine 

 insects being adapted to the Danaine species. If we trace the species or races allied to 

 H. Numata over the whole of Tropical America, we shall find that each one mimics a 

 Danaine species in its locality ; and I think it probable that they are all of the same stock 

 as H. Numata. Thus, in Eastern Brazil H. Ethra mimics Ilechanitis Nescea ; and in the 

 southern parts of the same country, S. Eucrate precisely imitates Ilechanitis Lysimnia. 

 I have already mentioned these and other cases occurring in New Granada, Nicaragua, 

 Eastern Peru, and the Upper Amazons : the Heliconii are adapted sometimes to a Me- 

 chanitis, and sometimes to a Melinma. 



H. Numata varies in structure as well as in colours. The wings are sometimes broader, 

 sometimes narroAver ; and their edges are simple in some examples, and festooned in others. 

 The yellow crossbelt is sometimes blended with the ground-colour of the wing ; in many 

 examples which connect the species with H. Eucoma it is narrow, and in others very 

 broad, as represented in Cramer's figure. 



The central black stripe of the hind wing is often very broad, covering part of the cell ; 

 at other times it is very narrow, and passes much behind the cell. 



The species is found abundantly throughout the Amazon region ; it occurs in thinned 

 parts of the forest, where it is seen sporting about by twos and threes in the sunlight, or 

 floating lazily in the air. The following is a remarkable variety occurring only on the 

 Upper Amazons. 



Var. H. Isabellinus. 



cj 5 similar in shape and in the position of the black markings to H. Numata. Pale 

 orange-tawny ; in the fore wing the two macular belts, which in S. Numata are distinct 

 and of a yellow colour, are blended together and of the same pale orange-tawny hue as 

 the rest of the wing ; the nervures, at the point where the two belts touch, are margined 

 with blackish ; the apical part of the wing is black, as usual, and is crossed by a row of 

 four pale spots. 



Two examples occurred, one at St. Paulo, and one (much smaller) at Tunantins. 



3. Hblicgnitis Eucoma, Hiibner. 

 Eueides Eucoma, Hiibner, Zutrage, f. 577? 578. 



This species differs from IL. Numata in the yellow crossbelt of the fore wing being 

 narrow and submacular, consisting of four or five more or less distinct elongate spots, 

 and also by its being separated from the cell by a series of black spots, more or less joined 

 together in the form of an oblique belt. It is, however, extremely variable. At St. 

 Paulo and other stations on the Upper Amazons, many examples occurred of a very dark 



