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IV. On Specific and Mimetic Relationships in the gen/us 

 Heliconius, L. By H. Eltringham, M.A., D.Sc, 



F.Z.S. 



[Read March 1st, 1916.] 



Plates XI-XVII. 



Some time has elapsed since Professor Poulton first 

 suggested to me that an investigation into the specific 

 relationships of the forms of the genus Heliconius would 

 probably be productive of interesting results, and I must 

 admit to having had some hesitation in embarking on such 

 a work in view of the fact that a very lengthy and elaborate 

 monograph of the genus already existed. This memoir, 

 however, is based entirely on external characters, and it 

 appeared that anatomical study might elucidate new facts 

 with regard to the relationships of the forms, more especially 

 as the mimetic phenomena are of an unusually complicated 

 kind. 



Perhaps the most valuable feature of the monograph 

 above referred to (Stichel and Riffarth, in " das Tierreich," 

 1905) is the recognition by Riffarth that the whole genus 

 can be divided into two sections by means of a peculiar 

 character of the fore-wing underside in the male. It was 

 my friend, Mr. W. J. Kaye, who pointed out * that, having 

 divided the forms by means of the character mentioned, 

 a most remarkable fact was disclosed. 



A great number belonging to Section I resemble very 

 closely forms belonging to Section II. In other words, 

 intrageneric mimetic resemblance is of frequent occurrence 

 I here use the words " mimetic " resemblance in a wide 

 sense as indicating merely a similarity of pattern; the 

 precise nature of the resemblance may be considered later. 



The present paper is an attempt to investigate more 

 precisely the specific relationships of the forms of Helicon I us 

 by means of anatomical study combined with an examina- 

 tion of pattern gradations. 



AVe are rarely able in such investigations to arrive at 

 entirely satisfactory conclusions owing to lack of adequate 



* True. Hut. Sue. Lend., p. xiv, 1907. 



TRANS. ENT. SOC. LOND. 1910. — PART I. (AUG.) 



