538 Appendix. 



sharply defined families, the Acrceida and the butterflies 

 of the Maracuja group. 2 The latter comprises the three 

 genera Heliconius, Eueides, and Col&nis, which differ 

 only in very unimportant characters ; Eueides is dis- 

 tinguished from Heliconius by its shorter antennae, and 

 Colcenis differs from Eneides in having the discoidal cell 

 of the hind-wings open. The genus Dione is further 

 removed by the different structure of the legs, and the 

 silvery spots on the underside of the wings. Certain 

 species resemble those of other genera in a most striking 

 manner, and much more closely both in colour and 

 marking, and even in the form of their wings, than they 

 do their own congeners. This is the case with Acrcea 

 Thalia and Eueides Pavana, with Heliconius Eucrate and 

 Eueides Isabella, and with Eueides Aliphera and Colcenis 

 Julia, which are deceptively alike, and the last two are 

 connected with Dione Juno, at least by the upper side of 

 the wings. The difficulty of judging of the relationships 

 of the single species is thus much aggravated ; it cannot 

 be said how much of this resemblance is to be attributed 

 to blood-relationship, and how much to deceptive 

 imitation. 



" As larvae all the Brazilian species must be placed in 

 one genus, as they agree exactly in the number and 

 arrangement of their spines (4 spines, not in a transverse 

 row, on segments 2 and 3 ; 6 spines, in a tranverse row, 

 on segments 4 n ; 4 spines, not in a transverse row, 

 on the last (i2th) segment). They differ from one 

 another much less in this respect than do the German 

 species of Vanessa, such, for instance, as V. lo or Antiopa 

 from V. Polychloros, Urticce, and Atalanta? The larvae 

 of Acrcea Thalia are certainly without the two spines on 

 the head which the others possess, and, on the other 

 hand, they have a well-developed pair of spines on the 



1 [Maracuja, the local name for the Passiflora. R.M.] 



See p. 448. 



