812 MR. R. I. POCOCK ON THE 



their appeai'auce, chase tliem with eager speed, catch them in 

 mid -air with precision, and eat them or taste them with avidity. 

 (2) Pursued butterflies when overtaken often avoid the birds, 

 not once only but twice or three times, by sudden turns up or 

 down to right or left. 



Those who hold, ou the negative evidence above stated, that 

 birds are not to be reckoned as serious enemies of butterflies, 

 must be called upon to supply some explanation other than that 

 above proposed of the marked reactions between these two 

 classes of animals when brought into contact with one another, 

 and to show reason why what ta,kes place in the aviary may 

 not be regarded as indicative of similar occurrences in nature. 



With regard to the experiments on mimicry, especially those 

 made with Volitcella hombylans and Bomhus liortoritm, it appears 

 to me that they satisfy all that the theory, as propounded by 

 Bates, demands. They fully confirm Prof. Lloyd Morgan's experi- 

 ments on birds, with the drone-fly [Eristalis) and the honey-bee 

 (Apis mellifiGa), as well as those with the banded and uncoloured 

 slips of glass holding respectively meal adulterated with quinine 

 and meal untampered with,* They show that several species 

 of birds, after learning by experimental tasting that Bombus 

 hortorum is unpalatable, refused to touch Volucella hombylans. 



Other items of interest that may be briefly alluded to are the 

 experiment demonsti'ating, at least in the instance tried, the 

 attractive nature of the ocelli on the wings of the peacock butterfly 

 {Vanessa io) ; the experiments showing that Formica rufa is not 

 protected from mammals and birds by its acid taste ; that the 

 black members of the Carabidse and Ocyptis olens are inipalatable 

 to the ground-feeding mammals they were offered to ; that 

 Coccinella 7-punctata and the Telephorid beetle (? Rhagonyche 

 fulva) — belonging to faniilies of beetles which are common 

 objects of mimiciy in the tropics — are distasteful to nearly all 

 mammals and birds. 



At the end of the part of the paper describing the experiments 

 made, I have added, at Dr. LongstafF's suggestion, for the informa- 

 tion of those unfamiliar with the habits and distribution of the 

 mammals, birds, and reptiles to which the insects and other 

 invertebrates were offered, a list of the species of the former 

 groups giving a few particulars on those points. 



Final l}^ I have to thank Prof. Poulton for kindl}^ annotating 

 the paper before it went to press, and for explaining more fully 

 than I could do the bearing of some of the results on the 

 theories of mimicry and of the connection between palatability and 

 coloration. I am also indebted to Commander J. J. Walker, R.N., 

 for kindly giving me the scientific names of the Lepidoptera. 



* Animal Behaviour, pp. 164-165, 1900, 



