Ristcrn Picridce. 309 



variety of causes and changes, organic and inorganic, acting and 

 reacting througliout all preceding ages. It is, therefore, no objec- 

 tion to a theory that it does not explain everything, but rather 

 the contrary. A true theory will certainly enable us to under- 

 stand many of the phenomena of life, but owing to our necessarily 

 imperfect knowledge of past causes and events, there must always 

 remain complicated knots that we cannot disentangle, and dark 

 mysteries on which we can throw but a straggling ray of light. 



The Eastern Plerklce present us with none of those wonderful 

 cases of mimicry which characterize the American genus Leptal'is, 

 and whose perfection enabled Mr. Bates to arrive at a satisfactory 

 explanation of the phenomenon. The comparatively small range of 

 colour and marking in the genera Euplcea and Dnna'is offer few 

 facilities for that first accidental approximation which is the neces- 

 sary groundwork for the production of a more perfect resemblance. 

 Nevertheless there are a few interesting cases which I think must 

 come under the head of mimicr'y. The first is that of the Eastern 

 species o( Eronia, the females of which all approximate, more or 

 less, to the markings of the genus Danais. The particular cir- 

 cumstance that makes it probable that this is a true case of 

 mimicry is, that in several species a variety of the female occurs 

 with the base of the hind wings bright yellow, exactly correspond- 

 ing to the colour of other species of Danais, Thus in Malacca 

 and Sumatra the ordinary dark female of Eron'ia Valeria mimics 

 Danais similis, while the yellow variety is like Danais philomela. 

 In the Moluccas and New Guinea the dark females of Eronia 

 argolis and Eronia iohcea are like Danais sobrina and Danais me- 

 ganira, while the yellow varieties resemble Danais cleona and D. 

 gloriola. 



There seems, however, to be a group within the family of 

 Pier/c/te itself which is the subject of mimicry. This is the genus 

 TInjca, which comprises the most gay and variegated species, and 

 is very abundant both in species and individuals, which are almost 

 entirely confined to the forests, and have a very slow and weak 

 mode of flight. They arc, therefore, singularly parallel to the South 

 American Heliconiidce, and probably like them have some special 

 protection which renders escape by flight less necessary to them 

 than it is to the species of allied genera. That this is the case is 

 rendered more probable by the fact that I can point out four 

 species of other genera that resemble them most curiously in 

 details of colouring : Prioncris thcstylis has the under surface 



