( 2 ) 



directed against the theories of mimicry was to the effect that, 

 on the whole, birds did not destroy butterflies to any appreci- 

 able extent ; he had therefore collected together all the available 

 evidence bearing on the question. As indicating the extent of 

 such observations, it was stated that these records refer to a 

 considerable number of species of both birds and butterflies, 

 as might be judged from these approximate figures : Palaearctic 

 Region : 33 birds, 34 butterflies ; Ethiopian : 26 birds, 26 

 butterflies ; Oriental : 27 birds, 46 butterflies ; Nearctic : 

 46 birds, 20 butterHies. Unfortunately in the Neotropical 

 Region, from which the greatest amount of evitlence might 

 have been expected, such exact observations had been almost 



[viii 

 entirely neglected. It was contended that the negative evidence 

 on this subject, which appeai^ed to have been very generally 

 accepted, was really of very little scientific value, because in 

 no case had it been shown that the observer had any adequate 

 knowledge of the actual food-habits of birds, or that any 

 careful and exhaustive inquiry had been made into the subject. 

 Instances were also cited to show how very easily destruction 

 of this kind might be overlooked ; while negative evidence 

 derived from an examination of the contents of birds might 

 be very misleading, owing to the fact that in so many instances 

 the butterflies' wings are not swallowed, so that any recognition 

 of the remains becomes extremely difficult. Finally, it was 

 urged that the large body of evidence resulting from merely 

 casual observations indicated that the assumption that bii'ds do 

 not eat butterflies to any extent is certainly prematui-e, and 

 that a fuller inquiry will probably show it to be entirely 

 unfounded. 



A discussion followed in wliicli Mr. A. W. Bacot, Mr. H. 

 Rowland-Brown, Mr. II. Main, Mr. A. E. Tonge, Mi-. H. M. 

 Edelsten, Mr. J. W. Tutt and other Fellows, gave their 

 experiences on the subject, Mr. W. Sharp suggesting that 

 the actions of the sparrow, as a domesticated bird, was not 

 evidence foi- conditions which exist in the case of purely 

 natural species. Di-. T. A. Chapman suggested tliat the paucity 

 of observations on the point was largely due to tlie shyness of 

 birds eating in the presence of human beings. Mr. W. J. 

 Kaye said that he had never observed birds attacking butter- 



