320 
COLOUR IN NATURE 
CHAP. 
dayi the same contrast of colour is observed—yellow 
in the Javan P. Coon, and red in the Indian P. 
Doubledayi. Wallace regards this as a proof of 
mimicry, the mimicking forms varying as the 
mimicked forms vary; Piepers regards it as a 
response to similar geographical conditions, and 
denies specific value to the forms Coon and Double¬ 
dayi, as also to Mernnon and Androgeos. The case 
shows considerable resemblance to the one which he 
next considers, and which may be briefly noticed. 
Among the Satyridae there are two closely related 
species, Paraga Egeria and P. Megcera, both common 
in Western Europe, of which the former frequents 
shady woods and the latter exposed places, especially 
the neighbourhood of walls heated by the sun. The 
colour of the first is a dull brown, with dull yellow 
spots, of the second a bright reddish-orange. When 
traced southwards, however, the tint of P. Egeria 
deepens and approaches more closely to that of P. 
Megcera . In Java there are two species of Junonia, 
J. Erigone, and J. Asterice, belonging to the Nymph- 
alidae and certainly not closely related to the above, 
which have respectively similar habits and colora¬ 
tion. Here, then, is one of those cases of duplex 
“ mimicry,” so dear to the hearts of many, spoilt 
only by the trifling circumstance that the two sets 
are separated by the distance of nearly half the 
globe ! 
This paper has been quoted at such length, not 
because it is the only detailed criticism of mimicry 
extant, but because of the care with which it is done, 
and the apparent strength of its criticisms. Very 
few of the instances of mimicry have been subjected 
