538 Mr. H. W. Bates on Butterflies 
terior wing, but these were rare ; whilst at Montes Aureos 
the intermediate forms seem to be as common as the two 
extreme forms. On the Lower Tocantins, and on the 
Lower and Upper Amazons, I met with no intermediate 
varieties. 
Heliconius Melpomene, H. Thelxiope, and intermediate 
varieties. 
Mr. Belt’s collection adds considerably to our know- 
ledge of the curious local distribution of these allied 
forms of Heliconius. In my paper on the Heliconiide, 
already alluded to, I stated that Heliconius Thelxiope was 
confined in its distribution to the alluvial plaims of the 
Amazons, and H. Melpomene to the more elevated con- 
tinental land to the North and South of these plains ; and 
I argued, that as a series of connecting links between the 
two distinct types was found at several points on the 
margin of the low plains, we might fairly infer that one 
of them was derived from the other by variation and 
natural selection ; H. Thelwiope bemg probably originally 
an extreme variety of H. Melpomene, strayed into the low 
humid forests, and, becoming adjusted to the new condi- 
tions of hfe there, spreading, in course of time, as a 
distinct form, from end to end of the region. Since my 
paper was published, Mr. W. W. Saunders has exhibited 
to the Society (see Proc. Ent. Soc. 1866, p. 11.) a fine 
series of these intermediate varieties which he had re- 
ceived from Cayenne, where the extreme form H. Thelxiope 
does not appear to occur, although there are varieties 
nearly approaching it. The results of Mr. Belt’s investi- 
gations confirm what I had observed with regard to the 
distribution of the forms. He tells me that H. Thelxiope 
did not occur in the Montes Aureos district, but that 
H, Melpomene was abundant between there and Maran- 
ham, and was found withm three miles of his locality ; 
whilst at Vizeu, on the coast, nearer the Parad river, he 
found numerous forms intermediate between the two 
species, neither of which was there present. This accords 
with what I observed at Serpa, on the borders of the Guiana 
highlands, which there form the northern banks of the 
Amazons, and at one place on the river T'apajos. — It also 
confirms what I have stated, that hybridity has little 
or nothing to do with the production of these imter- 
