252 THEORIES OF MIMICRY 1 



usual in Coleoptera, the legs are slender and wasp-like, 

 and are moved with wasp-like activity and jerkiness. In 

 spite of the apparent want of wings, the effect produced 

 is very considerable, and the majority of persons would 

 hesitate to touch the insect. This, then, is the method 

 adopted in the group of Clylinae ; but in various other 

 allied tribes, such as the Nccydalinae, the Rhinotraginae, 

 the Esthesinac, the Callichrominae, and others, the elytra, 

 which form by far the largest part of the visible dorsal 

 surface in the Clytinae, become greatly reduced so as to 

 show the under wings, which, folded over the back or 

 expanded in flight, in either case strongly suggest the 

 wings of a wasp, or in some cases an ichneumon. 

 Furthermore, the elytra are reduced in two different 

 wa y S — m some genera to linear rudiments more or less 

 broadened at their bases ; in others to small subquadrate 

 or oval structures representing the bases alone. 



We thus find that wasps and allied forms are resembled 

 by species of many groups of insects, and the resemblance 

 is attained in all kinds of different ways. 



The numerous mimetic resemblances to the aggressive, 

 abundant, and well-defended ants supply an even better 

 illustration. In the majority of mimics the whole body of 

 the mimetic form is moulded from the ancestral shape- 

 still exhibited by non-mimetic allies — into that which is 

 characteristic of an ant. In some groups this means a 

 large amount of alteration, in others less. In this case, 

 too, the resemblance extends to forms which are alto- 

 gether outside the Insecta ; for many small species of 

 spiders closely mimic ants. In the family of Attidae 

 alone — and such resemblances occur in other families of 

 spiders — George W. and Elizabeth G. Peckham state 

 that about a hundred ant-like species are known from 

 various parts of the world, and that they are * very much 

 more numerous in South America and in the Malay 

 Archipelago than in any other countries', 1 viz. in the 

 very countries in which other examples of Mimicry are 

 especially abundant. The spider with its two-fold division 



1 Occasional Papers of I he Natural History Society of Wisconsin, vol. ii, 

 1892, Milwaukee ; see also a paper by the same authors in vol. i, 1889. 



