342 THE PLACE OF MIMICRY 



change. Furthermore, the males of four species of 

 Teracolus (achine, omphale, evenina, antigone) are often 

 nearly indistinguishable in the dry season but can be 

 separated at a glance in the wet. The same comparison 

 holds, but to a less extent, with the females of the dry 

 and wet broods. A similar relationship obtains in two 

 Indian species of the Oriental and Austro- Malayan 

 Pierine genus Htiphina, H. nadina and H. phryne. 



It is impossible to leave this part of the subject without 

 alluding to the European Nymphaline butterfly, Araschnia 

 levana and its later form prorsa, investigated by Weis- 

 mann, and proved by him to be susceptible to the 

 stimulus of temperature in the pupal stage. It has been 

 suggested that the black white-marked form prorsa is 

 mimetic of the species of Limenitis (White Admirals), 

 which, although larger, possess a pattern of the same 

 general type on both upper and under surfaces. The 

 earlier brood levana has been similarly compared to a 

 small Fritillary. If these suggestions be confirmed we 

 should witness a seasonal transition in the kinds rather 

 than the degrees of Mimetic and probably Synaposematic 

 Defence. 



7. The Gradual Predominance of the Milllerian 

 Hypothesis. — A brief history of the discovery of Miil- 

 lerian Resemblances among the butterflies of South 

 America, the East, and finally of Africa, has been given 

 on pp. 222-3 ; their extension to explain the uniformity 

 in the species of distasteful groups, and the resemblances 

 between the Warning Colours of all kinds of forms in the 

 same country, is referred to on pp. 230-4. A fuller 

 statement of the essential differences between the rival 

 hypotheses will be found on pp. 211-15. 



Reasoning, based on the investigations of the last 

 1 3 years, has tended more and more to remove exam- 

 ples from the category of Batesian (Pseudaposematic) 

 Mimicry and transfer them to that of Mullerian (Synapo- 

 sematic) Resemblance. Thus almost the whole of the 

 butterflies and moths shown in the lecture before the 

 British Association (1890) as examples of Batesian 

 Mimicry would now be looked upon as instances of 



