( ^ ) 



are very rare, and at any rate much more scarce than their 

 models * : where they are equally abundant, as in the 

 well-known case of the Galerucid genus Aulacophora and the 

 Longicorn genus Astathes, the mimicry is probably always 

 Mullerian. 



10. The question of Mullerian mimicry is a very large 

 one, and in the brief space left at my disposal it is impossible 

 to say much about it : I hope that I may be able to deal 

 with the subject at greater length on a future occasion. In 

 the first place, what is meant by the term 1 What is Mullerian 

 mimicry 1 is a question often asked by people who claim 

 to have and perhaps have a considerable knowledge of the 

 general subject ; and this is scarcely to be wondered at, for 

 it is very hard to exactly define the term ; originally it was 

 applied to the case of certain distasteful f butterflies which 

 closely imitated one another and by this means halved the 

 injuries done to the total number by the experimental attacks 

 of birds or other enemies : by this means the numerically 

 smaller genus obtained a great advantage in the struggle for 

 existence and probably in some cases escaped extermina- 

 tion : soon, however, it was seen that the principle was capable 

 of wide extension, and it may now perhaps be defined as " a 

 general resemblance throughout a large series of distasteful 

 or specially protected species, belonging to the same or 

 different genera, families, and orders, in a simple scheme of 

 aposematic or warning coloration;" hence we get the term 

 " Synaposematic or Common Warning Coloration." 



As it is necessary for the whole theory of Protective 

 Resemblance and Mimicry, etc., to prove that insects are 

 subject to the attack of birds and other enemies, so it is 

 necessary for the establishment of the Mullerian theory to 

 prove that these enemies, birds especially, do gain their know- 

 ledge by actual experience and not instinctively. I think 

 that this may be taken as conclusively proved by the researches 



* This is the case with the Longicorns belonging to the genera 

 JEgoprepis and Ectatosia from Borneo which imitate the much commoner 

 Brenthid Diurus furcillatus. 



t The term " distasteful " is much to be preferred to " inedible " : it is 

 doubtful whether any insects are really inedible ; even the most distasteful 

 are apparently eaten under stress. 



