74 Darwin- Wallace Celebration. 



better protected of the two. This protection against insect-eating 

 enemies may be> effected (1) by a general duluess or darkness or 

 coloration, tending to concealment ; or (2) by a cryptic resemblance 

 to some inanimate object, such as a dead leaf; or, finally, (3) by 

 mimicry of some distasteful insect, often belonging to a widely 

 different group. 



Examples of all these methods are shown, and the fact is illustrated 

 that the males may in *ome cases take no share in the means of 

 defence adopted by the females, while in other cases they enjoy a 

 similar provision against attack, but in a lower degree. 



Exhibited by Dr. F. A. DIXEY. 



iii. A series of Melanilis leda, Linn., taken at Curepipe, Mauritius, 

 March to December, 1905, arranged in the order of capture. 

 The variability of the Underside of the Butterfly is shown as 

 well as the effect of season : in the wet season ocelli are usually 

 more marked, in. the dry season the underside is usually more 

 leaf-like. 



Exhibited by Col. N. MANDEBS, R.A.M.C. 



iv. Scents in Butterflies. 



(a) Agreeable scents, presumably attractive, usually confined 

 to the male. 



(6) Disagreeable scents, presumably repulsive, usually common 

 to both sexes, but often more pronounced in the female. This 

 group includes many species known to be distasteful to insecti- 

 vorous animals. 



[The flowers, or other objects, to which the scents have been 

 compared were indicated in red.'] 



Exhibited by Dr. DIXEY and Dr. G. B. LOXGSTAFF. 



v. The apparent " two heads " of the Lyccenidce. 



Many Blues and Hairstreaks rest with the head downwards, 

 but the peculiar structure and marking of the hind-wings give 

 the appearance of a head with antennae at the tail end of the 

 Butterfly. This doubtless often deceives their enemies, accord- 

 ingly many Lycsenids are captured which bear evidence of 

 having escaped with their lives by the loss of their "false- 

 heads." 



