BODILY CHARACTERISTICS CONSPICUOUSNESS 313 



where the various species are mimicked by a number of edible 

 Butterflies belonging to other families. 



Mimicking Moths. The three groups of Lepidoptera so far 

 mentioned are by no means the only ones which are more or 

 less endowed with noxious properties, as a result of which they 

 have been the subject of imitation by their cousins. Cases among 

 Moths are known even among British forms, the most familiar 

 example being that of the White Ermine Moth (Spilosoma 

 menthastri), which is copied by the female of the Muslin Moth 

 (Diaphora mendica). The colour is white, spotted with black, 

 and the species imitated is known to be unpopular among insect- 

 eating animals. 



Clear-wing Moths. Some of the adult Lepidoptera imitate 

 members of other orders better endowed than they are with 

 means of defence. A very good instance of this is afforded by 

 the " clear- wing" Moths, so-called because the wing-membranes 

 have to a large extent lost the covering of scales which is so 

 characteristic of the lepidopterous order. Our two native species 

 of Hornet Clear- wing (Trochilium apiformis and T. crabroni- 

 formis), for example, look very like Hornets as a result of this 

 special character, with accompanying modifications of the pro- 

 portions, colours, and markings of the body. It is even stated 

 that when caught they make a pretence of stinging. That this 

 is really a case of mimicry is, however, doubted by some natural- 

 ists, as, e.g., by Sharp, who, speaking of the Clear- wing family (in 

 The Cambridge Natural History), says: "Some of the species 

 have a certain resemblance to Hymenoptera, which is probably in 

 most, if not in all, cases merely incidental ". 



Mimicking Caterpillars. The larvae or caterpillars of a num- 

 ber of Butterflies and Moths would appear also to be protected 

 by mimetic devices, including more particularly the assumption, 

 when frightened, of alarming or warning attitudes of deceptive 

 nature. A remarkable case is that of the caterpillar of the 

 Lobster Moth (Stauropus fagi) (fig. 488), which, under ordinary 

 circumstances, is more or less protected by its resemblance in 

 colour and form to a distorted and withered leaf. When alarmed, 

 however, it rears up the ends of its body and vibrates, presenting 

 a sort of bogey-like aspect, which may be described as half spider- 

 like with the other half bug-like. Another remarkable caterpillar 

 is that of the Puss- Moth (Cerura vinula), which, when frightened, 



