Cryptic resemhlance of two South American Insects. 535 



was more roughly produced by means of light, strongly 

 reflecting, opaque body-colour is in some respects clearer 

 in this moth than in butterflies of the genus Kallima. 

 The presumably older less realistic method is found in the 

 small patches placed nearest the base of the fore-wing, 

 and in the small distinct patches bordering the lenticular 

 nearly closed bay between fore- and hind-wing. The 

 large irregular network of areas grouped round the anal 

 angle of the fore-wing is clear and transparent over the 

 greater part of its extent, but the meshes nearest to the 

 anal angle itself are far less transparent, being covered 

 with pale pigmented scales. On the hind- wing, apart 

 from the border of the lenticular bay, the same contrasted 

 stages of evolution are even better seen. Thus the anal 

 network of areas is pale-coloured over its anal half, trans- 

 parent over the other half. Of the network at the base 

 of the winw the three meshes — two larjije and one small — 

 nearest to the inner margin are pale, the others trans- 

 parent. A small isolated area coming to the very edge of 

 the inner margin between this network and that last- 

 named, is unusually opaque, but even this lets through 

 a little light. The distinction between the two methods 

 by which transparency is suggested can, in some cases, be 

 made out in the representation given in Fig. 1, Plate 

 XXXII. Thus the small basal pale patch of the fore- 

 wing can be recognized as somewhat different from the 

 transparent areas of the network which lies next to it. 

 Transition is easy ; for the pale reflecting areas are also 

 transparent, although to a much less extent than the 

 others. We can apparently recognize four sta.ges in the 

 evolution of the clearest and most transparent areas of 

 "Bmeenta: — (1) Opaque white strongly reflecting pig- 

 ment, employed as an artist would use " body-colour " to 

 suggest the bright light coming through a hole, (2) The 

 pigment becomes less opaque and semi-transparent ; so 

 that some effect is produced when the surface of the wing 

 is in deep shadow with a bright light on the other side of 

 it. (3) The scales lose their pigment and become com- 

 pletely transparent. (4) The scales assume a more up- 

 right position so that most of the light passes between 

 them; in the fullest development of this stage they 

 become vertical. The second and fourth of these stages 

 are very evident on part of the wing of this interesting 

 moth and I think the third is also present. Some of the 



