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



An allied species, H. Thelxiope of Hiibner, exists there in its stead, having very similar 

 habits, and filling, as it were, the same sphere in the economy of nature. These two 

 fprms {S. Ilelpomene and H. Thelxiope) have all the appearance of two thorouglily 

 distinct species; but they are connected together by an unbroken series of varieties, 

 the principal of which occur, not in the places where the two species come in contact, 

 but in two isolated limited areas— at Serpa (west of Obydos) and on the banks of the 

 Tapaios (near Aveyros). These connecting links cannot be the hybrid progeny of two 

 orio-inally distinct species, on account of their geographical position; many of them 

 (and others not met with on the Amazons) occur also in Surinam and Cayenne, where 

 H. Thelxiope has not been found. I believe there can be no doubt that S. Thelxiope 

 is descended from S. Melpomene, and that the intermediate varieties are remnants of 

 the steps of modification. The folloAving are the principal intermediate varieties ; they 

 are all very scarce, whilst the species they connect exist in great profusion : — 



Var. 1. H. Callycopis, Cramer, Pap. Exot. t. 190. f. E, E. 



Same as H. Melpomene, except that the red belt of the fore wing is either very broad 

 and irregular, or is broken into a number of various-sized spots. 



Surinam and Obydos, Lower Amazons, in company with H. Melptomene. 



Var. 2. H. Elimcea, Erichson, in Schomburgk, Reise in Brit. Guiana, p. 595. 



The same as Callijcopiis, except that, in addition to the irregularity of the red belt, the 

 basal part of the fore mng has a large red patch. 



Obydos, in company with H. Melpomene. 



Var. 3. H. Lucia, Cramer, Eap. Exot. t. 350. f. E, E. 



Same as H. Melpomene, except that the red crossbelt of the fore wing is narrow and 

 curved outwards, and that there is a large quadrate yellow spot within the end of the 

 cell. This is the commencement of the chain of variations which leads to H. Thelxiope. 

 The H. Lucia of Cramer was found at Surinam. I have Amazonian examples, taken at 

 Serpa and on the Tapajos, which difl'er in the yellow spot of the cell being scarcely 

 perceptible. 



Var. 4. The same as H. Lucia, except that the base of the fore wings has a large red spot, 

 and that the base of the hind wing is also red. 

 Serpa, Lower Amazons ; banks of the Tapajos, near Aveyros ; Cayenne. 



Var. 5. H. Ertjthrcea, Cramer, Pap. Exot. t. 189. f. A. 

 Santarem, in company with H. Melpomene ; Surinam. 



Var. 6. S. Andremona, Cramer, 1. c. t. 297. f. A. 

 Surinam. 



