( 19 ) 



universal custom with bii-ds, and so did not mention the fact ; 

 they always swallowed the excrement before flying off. It is 

 a curious habit, and in this case I am sure it was not done 

 from hunger."] 



Professor E, B. Poulton said that the bulbul was probably 

 little affected by properties which were a protection against the 

 majority of insect-eating birds. Mr. Andrewes' observation 

 helped us to a knowledge of the special enemies of specially 

 defended insects, and was further evidence of Haase's error 

 in applying the unqualified term " immune " to any insect, 

 however unpalatable. Monsieur Charles Oberthiir had argued 

 "(Etudes de Lepidopterologie comparee" : Fasc. ii, Rennes, Oct. 

 1906, p. 25-27) from cases such as these that there is no 

 significance in any special defence or the accompanying 

 warning (aposematic) colours. This distinguished naturalist, 

 xxxiiil 



seeing in nature that every living being served as the ood of 

 some other being, arrived at the conclusion that the order of 

 things is fixed and unchanging, and that by sux'e instincts and 

 keen senses the insect-eating animals found their prey, un- 

 hindered by concealment or by any other mode of pi'otection. 

 M. Oberthiir believed in short that the very words " conceal- 

 ment " and " protection " only represent an unsound anthropo- 

 morphic inference, for, in his opinion, neither concealment nor 

 protection from enemies is ever afforded. From a study of the 

 same struggle for existence the majority of naturalists have 

 come to very different conclusions. They saw evidence for 

 the existence of a balance between the aggressive and pro- 

 tective forces, and believed that in maintaining this balance 

 cryptic colours and warning and mimetic patterns were of 

 essential importance to numberless species. They recognised 

 the usual ultimate success of the enemies of insects, but also 

 saw that this success involved hard work and much time spent 

 in the chase, and that in fact the relationship between pursuer 

 and pursued was precisely of the kind to strengthen the faculties 

 and powers of the one and gradually impi"ove the protective 

 methods of the other. 



Professor E. B. Poulton also exhibited two female specimens 

 •of Laphria gilva, L., captured with prey (Sept. 1906) at 



