Notes on Brazilian Entomology. 



It has been suggested that the production of sound by Ageronia is connected 

 with the existence of a small membranous sac at the base of the front wings, 

 which in the living insect is filled with air when te costal nervure is compressed. 

 But this sac also exists in several other butterflies, which seem to be incapable 

 of producing sounds, e. g., Pyrrhogyra Edocla and Callicore Ehiina. If I re- 

 member rightly, in Eunica Margarita the sac is wanting. 



Insects distinguishing Colours. 



In flowers with changing colours, most of the visiting insects perfectly 

 distinguish the first honey-filled flowers, as I have ascertained by a long series of 

 observations on some species of Lantana. In some species the difference in colour 

 between the fresh flowers and the older ones is but very trifling, a small yellow 

 circle surrounding the entrance to the tube of the corolla during the first day and 

 disappearing afterwards. 



A specimen of Victorina Frayja was lately observed settling on the flower 

 of a rose-tree painted on a wall; the painter was much pleased by seeing his 

 skill thus acknowledged by that butterfly. 



Mimicry. 



In some years, as I stated in 1871, Mechanitis Lysimnia is here hardly more 

 common than the imitating Leptalis Astynome', but in most years M. Lysimnia 

 is extremely abundant and L. Astynome rather rare. 



When I descended in a canoe the western branch of the Itajahy (December 

 i6th, 1876), small white butterflies were very common on the banks of the river: 

 all appeared to be of the same species. I caught about a dozen, and on examining 

 them at home found them to be Leptalis Nehemia, which so wonderfully mimics 

 a Pieris, that even Boisduval was deceived and described as Pieris Nehemia. 

 Now, in his case, the model must have been either by far more rare than the 

 copy, or entirely wanting. 



On the Itajahy we have three species of Eueides, viz., E. Pavana, Isabella 

 and Aliphera; all of them are rare, and E. Pavana extremely so. This last 

 species closely resembles Acrcea Thalia; E. Isabella resembles Meclianitis Lysimnia 

 and Heliconius Eucrate, while E. Aliphera mimics Colcewis Julia. I, therefore, 

 formerly thought that the three rare species of Eueides mimicked the three common 

 species of Acr&a, Mechanitis and Colcenis. Afterwards, after finding that the 

 several species of Eueides possess a very strong and repugnant odour, I had become 

 somewhat doubtful, and at Sao Bento I found that E. Aliphera was extremely 

 common, so common, indeed, that repeatedly I caught as many as eight specimens 

 in the net at once, whereas C. Julia was so rare that I have only seen two or 

 three specimens altogether. Thus, judging by their relative abundance, an observer 

 on the Itajahy might consider E. Aliphera to be a mimic of C. Julia, while an 

 observer at Sao Bento might take C. Julia to be a mimic of E. Aliphera. 



Correlation of Habit with Protective Resemblance. 



Any number of cases might be given. The case which has most struck 

 me is that of the caterpillar of a small moth belonging to the curious Cochliopod 



