114 



AFRICAN MIMETIC BUTTERFLIES 



The same experimenter found that while Delias eucharis was one of the most distasteful 

 of all butterflies to many species of Indian birds,^ in East Africa the moth Egybolis vaillantina 

 was refused by a chameleon and a gecko.^ Colonel Yerbury, on the other hand, observed 

 a mantis at Trincomali hanging from a flower and capturing the butterflies which were 

 attracted by it. He saw it eat Delias eucharis on several occasions.^ Mr. F. Muir found that 

 D. chrysippus was rejected by a mantis at Mozambique even when hungry. 



The most extensive and valuable experiments made in connexion with the bionomics 

 of butterflies and other insects are those which were carried out by G. A. K. Marshall in 

 South Africa. The results, together with most interesting and comprehensive comments 

 thereon, were published in a joint paper by Mr. Marshall and Professor Poulton and com- 

 municated to the Entomological Society in 1902.* This memoir occupies some 300 pages 

 of the Transactions, and is illustrated by fifteen plates. It is difficult to exaggerate the 

 importance of this paper, and to express the great indebtedness of students of mimicry to 

 the authors. To Mr. Marshall for his patience and conscientiousness in carrying on the work, 

 and to Professor Poulton for his valuable comments on the results attained. It should be 

 taken as a ' model for mimicry ' by all those who have the opportunity of making such 

 experiments, since the value of personal observations of this kind can hardly be over- 

 estimated. Mr. Marshall's experiments cover a very wide field of research, and include the 

 account of his well-known discovery with reference to the seasonal forms of Precis, together 

 with copious notes on a great variety of interesting observations. The value of the work is 

 greatly enhanced by numerous discussions on the results of the experiments and on subj ects 

 suggested by them. 



Mr. Marshall first investigated the butterfly-eating capacity of various species of mantis. 

 The distastefulness oiAcraea horta, even for a mantis, was shown by the fact that the insect 

 ' ran towards it, and seized it and made a bite at the back of the thorax, but started back 

 as if in great surprise, and wiped his mouth on his front legs '. On another occasion the same 

 mantis ' tackled it at once, seizing it from above and biting the thorax, but he quickly 

 let go and began wiping his mouth as before. A few minutes later he made a second attempt 

 with the same result '. Later on the Acraea was again placed close to the mantis, when he 

 began to eat it, but soon threw it down again, and would not touch it although no other 

 food was given for twenty-four hours. On another occasion a mantis, starved for twenty- 

 four hours, ate D. chrysippus all except the limbs. A third A. horta was caught and bitten 

 by the mantis, but it 'started back with disgust just as in the previous experiment, but his 

 efforts to get rid of the nasty taste were more prolonged. For over five minutes he con- 

 tinued cleaning his mouth on his fore-legs, or rubbing it from side to side on the gauze.' 

 Another mantis was given Acraea serena, but after biting it threw it down and ejected 

 a brownish liquid from its mouth, and also wiped its mouth with its legs. On another 

 occasion Acraea natalica was given, but after being bitten was dropped at once ; a second 

 attempt was made and the butterfly again dropped. Acraea serena was also rejected. 

 The mantis readily consumed other butterflies, including D. chrysippus, Charaxes varanes, 

 Papilio demodocus, Neptis agatha, Pyrameis cardui, and many others. The same insect 

 died after eating two chrysippus and one cahira, but whether as a direct cause cannot 

 be certainly concluded. Another species of mantis {Pseudocreobotra walberghi) after an 

 exclusively Acraeine diet, became paralysed in the mandibles and partially blind. The 



^ Journ. As. Soc. Bengal, 1897, p. 667. 

 2 ' Natural Science,' 1892, p. 747. 

 ^ Trans. Ent. Soc, 1902, p. 316. 



' Five Years' Observations and Experiments on 

 the Bionomics of S. African Insects,' Marshal and 

 Poulton, Trans. Ent. Soc, 1902. 



