Adaptive Mimicry. 63 



among the most striking instances of the phenomenon which 

 could be shewn, yet they are but isolated instances of a phenome- 

 non of which the vast extent has only recently been recognised. 

 A moment's obser.vation would suffice to shew that this mimicry of 

 a leaf and a twig respectively, would be invaluable to the insects 

 by enabling them at once to escape the notice of their enemies, 

 and to steal unobserved upon their prey ; and it is now known 

 that there are countless similar cases of a mimicry which is at 

 once protective and auxiliai'. Such instances ai"e not unknown 

 even among mammals and birds. Thus the little Malay Cladobates, 

 which is insectivorous, approaches its prey unsuspected, by being 

 mistaken for the harmless fruit-eating squirrel, and the resemblance 

 of the defenceless cuckoo to the powerful hawk, although it some- 

 times exposes the impostor to the attacks of a conspiracy of small 

 birds, tends powerfully to its protection and security in ordinary 

 circumstances. But it is of course among insects and smaller 

 creatures that such mimicry is most complete. Thus there are 

 green pipefish which fasten themselves to the bottom by their 

 prehensile tails, and wave about like harmless algae. There are 

 seahorses in Australia which assume the brilliant red colour, and 

 leaflike appendages of the seaweed among which they live. There 

 are spiders in Brazil that place themselves in the axils of leaves, 

 and assume so exactly the aspect of flowerbuds that they lurk uncon- 

 cealed and unsuspected in the very midst of their prey. The 

 Kallima, a butterfly of Sumatra, conceals its head and antenna), 

 and folding its wings so arranges them that the tails of the hind 

 wings touch the branch and give to the creature so exactly the 

 aspect of a shrivelled leaf and its stalk that even the most careful 

 observer is constantly deceived. The English Lappet moth would 

 at night run no chance of detection from a similar cause. Our 

 own little orange-tip butterfly when it is resting on the head of 

 some umbelliferous flower, in the evening, closely resembles it by 

 the green and white mottling of the under surface of its wings ; 

 the larva of the Peacock moth, with its pink spots and ground 

 colour, might well be mistaken for the heather buds on which it 

 feeds; the gorgeous colour of the day-flying summer butterflies often 

 enable them to escape detection among the flowers, while the night- 

 flying moths are similarly protected by their dusky tints on the 

 brown tree trunks, or by the grey, green, or silvery colours which 

 enable them to lie pertliis among the lichens that cover them. 

 The Specia apiforniis and other clear-winged moths get off harm- 

 less by their similarity to wasps and bees. Notice too that the 

 upper wings of butterflies are splendidly tinted and the under 

 wings double, whereas in moths it is often just the reverse, because 

 butterflies in repose shew the under and moths in repose the upper 



