Mimetic Relationships in the genus Heliconius. Ill 



We now pass to those species grouped under the name of 

 the 



Cydnoformes. 

 H. cydno, Doubl. 



The typical and eight subspecies are described with several 

 varietal forms occurring in Central America, Peru, Ecuador, 

 Colombia, and Venezuela. The claspers of five forms are 

 shown on PI. XV. They show a general resemblance of 

 structure with a certain amount of variation. 



H. weymeri, Stgr. 



Of the typical form of this Colombian species I have had 

 no example to examine, but have dissected out more than 

 one armature from the form gustavi, Staud. There is no 

 constant and recognisable difference between the armatures 

 of this and of cydno (PI. XV). 



H. pachinus, Salv. 



This species from Chiriqui and Costa Rica occurs com- 

 monly in collections. I have made several preparations 

 which show but little range of individual variation. The 

 pattern of the wings seems at first sight so distinct that it 

 might well be regarded as a satisfactorily defined species, 

 yet the armature (PI. XVI) shows no distinction from that 

 of weymeri and could not be constantly separated from 

 some forms of cydno. 



H. heurippa, Hew. 



This species, with which I include rubellius of Smith and 

 K i 1 by . occurs i n Colombia. Typical heurippa has a st ri k ing 

 appearance owing to the large patch of sharply divided 

 yellow and red on the fore-wing. In the form rubeUius 

 this patch is reduced to very narrow dimensions. The 

 clasper shown on PI. XVI from a specimen of heurippa shows 

 much the same structure as is found in cydno, weymeri, etc. 

 There can be little doubt that heurippa ami cydno are the 

 same species, and it will be seen later that consideration of 

 the pattern confirms this view. 



H. melpomene, Linn. 



Over fifteen subspecies of this form, with many varieties, 

 are described. They range over the greater part of 

 northern S. America, but have not. so far, been reported 



