The Bionomics of South African Insects. 337 



conclusion is suggested that Bates was mistaken in sup- 

 posing that Asilid flies play no part as the enemies of 

 Heliconinie and Ithomiinc'e. 



7. Lepidoptera with Warning Colours specially 

 liable to the attacks of parasitic insects, 

 (G. A. K. M.) 



[The late Erich Haase in his work on mimicry (English 

 translation " Researches on Mimicry," etc., Pt. II, Stutt- 

 gart, 1896) continually made the assumption that the 

 immunity of DanainiV; Acrmnai, and other specially-pro- 

 tected groups is absolute, and extends to the attacks of 

 parasitic Hymenoptera and Diptera as well as to those of 

 insect-eating vertebrates. A little reflection upon the rate 

 of multiplication of animals, and especially of insects, 

 makes it clear that any such absolute immunity is an 

 impossibility. A high degree of protection from the 

 attacks of the generality of insect-eating animals will 

 always be found to be compensated by the attacks of 

 special enemies, and jDrobably very largely by that of 

 insect parasites, I brought forward this argument in 

 1890 ("Colours of Animals," London, p. 181) ; and Haase, 

 without attempting to meet it, made the crude assump- 

 tions which will now be dismissed, once and for all, by 

 the numerous observations recorded below. — E, B. P.] 



Estcourt, Oct. 15, 1896. — We brought seventy-five 

 larva3 of Aerxa anacrcon home with us from Ulundi to 

 Estcourt, and no less than twenty of them were killed by 

 a Dipterous parasite, so that, although it may be protected 

 in the imago stage, the percentage of larval deaths must 

 be very high. 



Malvern, Feb. 21, 1897. — I certainly cannot understand 

 Haase's attitude with regard to protection from parasites. 

 There are such patent examples to disprove it among 

 European " whites." Out of eight pupa3 of Acriea horta 

 that I bred this season no less than five were killed by a 

 Dipterous parasite. 



[I have also received from Mr. Marshall two cocoons 

 and two imagines of an ichneumon bred from Acnea 

 cahira at Malvern. They bear the date April 1897. — 

 E. B. P.] 



TImhomaas Mouth, Natal ; Sept. 3, 1897.— I think it is 

 highly probable that ByUia ilithyia will prove to be dis- 

 tasteful as you suggest ; but so far as my experience goes 



TRANS. ENT. SOC. LOND. 1902. — PART III. (NOV.) 23 



