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THE NATURE BOOK 



proboscis, and are 

 built on stronger lines 

 than the Bombyliidce. 

 Unlike the latter, they 

 frequently settle. 

 Their resemblance of 

 certain species to the 

 Humble-bees, both in 

 furriness of body and 

 in colour arrangement, 

 is remarkable. Some 

 are clothed with red 

 hair at the extremity 

 of the abdomen, and 

 so mimic Bombits lapi- 

 dariiis, the common 

 Fire-tailed Humble- 

 bee ; others are 

 banded with sulphur 

 yellow and so resemble 

 Bombits terrestris or 

 Bonibiis I II com in. 

 Smooth-bodied Volit- 

 ccllcd often resemble 

 Wasps, V. inanis being 

 a good example. We shall recur later to 

 the fact that in VolucellcB the mimicry is 

 not only protective, but aggressive. 



To turn for a moment to other orders 

 of insects we find instances of a presumably 

 beneficial protective mimicry in the Clear 

 Wing Moths — I give illustrations of the 

 Hornet Clear Wing — and in several Beetles, 

 notably the common Wasp Beetle (C. 

 arietis), who, as Professor Poulton has 

 pointed out, exhibits, in addition to 

 wasp-coloration on the body, a decidedly 

 waspish character in the shape and 

 movements of the legs. In all the above 

 instances the simulation is of stinging 

 Hymenoptera, but protective mimicn,^ 

 has an almost unlimited range, and may 

 exist between creatures not only of 

 different orders, but of different classes 

 and even of different sub-kingdoms. Eye- 

 markings are a case in point, and I would 

 leave my illustrations to give some idea 

 of the terrifying aspect which these harm- 

 less arrangements of colour can produce, 

 more especially when, as in the case 

 of many Caterpillars, they are com- 

 bined with snake-like attitudes. It 

 would appear that the suggestion is that 

 there lurks behind the " eyes " a vertebrate 

 body of a size to correspond with them. 

 Spiders, again, and Ants, appear to be 



AN OFTEN QUOTED EXAMPLE OF 

 "WARNING COLORATION." 



The black-and-yellow caterpillar of the Cinnabar 

 Moth on its food-plant Ragwort. 



in themselves such 

 effective " bogies," as 

 to deserve the closest 

 possible imitation in 

 form. The caterpillar 

 of the Lobster Moth 

 on hatching from the 

 egg closely resembles 

 an ant. When full fed 

 his terrifying attitude 

 — he throws back his 

 head and brandishes 

 four skinny legs — 

 bears an extraordin- 

 ary resemblance to a 

 spider, and, it can 

 hardly be doubted, 

 must often intimidate 

 an Ichneumon Fly. 



From protective 

 resemblance, which, 

 strictly speaking, 

 merely effects conceal- 

 ment, we pass through 

 its specialised form 

 " protective mimicry," which decep- 

 tively suggests danger, to aggressive re- 

 semblance, defined by Professor Poulton 

 as " concealment in order to effect 

 attack," and to its offshoot "aggressive 

 mimicry." Under the latter heading come 

 appearances which " deceptively suggest 

 some object attractive to prey (alluring 

 colours), or which enable an enemy to 

 approach without exciting suspicion 

 (aggressive mimicry proper)." I am 

 pleased to be able to present an example 

 of " alluring colours," which I believe 

 has not hitherto been published, in the 

 case of a Spider of the genus Thomisiis. 

 This Spider {T. citrens) often mimics to a 

 nicety both in form and colour the buds 

 of the bramble, and the fly seen in some 

 of the illustrations had, immediately before 

 the photograph was taken, actually 

 perched on the back of " his bitterest 

 foe," but had found him inechble. Of 

 aggressive mimicry proper we have an 

 excellent example in the Volncellce already 

 referred to, whose wonderful simulation 

 of Humble-bees enables them to enter 

 the nests of the latter and deposit their 

 eggs there. Their larvc-e feed on the food 

 stored by the Bees, or even upon the Bee 

 larvae. Volncclla inanis is said to have 

 similar designs on Wasps' nests. 



