COCKROACHES, ETC. 129 



through the costal nervures of the fore-wings, but if the 

 position in which the Butterfly is held is not favourable 

 for this method of attack, the Mantis bites into the chest 

 of its prey so as to sever the wing muscles. A large 

 Butterfly when first seized will dash its attacker with 

 great violence against the sides of the cage in its mad 

 struggles for freedom, but I have never yet seen a Mantis 

 relax its hold, and by its tactics of severing either the 

 main ribs or else the muscles of the wings it soon 

 reduces its prey to impotence. 



Mantidce are very cleanly insects, and if during the 

 struggles of their prey they become plentifully dusted 

 with scales and hairs, their first action after a meal is 

 to rid their head and legs of these clogging atoms ; the 

 strong spines that arm the raptorial pair of legs are 

 picked over by the mandibles ; the antennae, too, are 

 combed clean by the same organs ; the middle pair of 

 legs are hooked up to the mouth by the raptorial claws 

 and held in position there whilst the pads of the tarsi 

 are licked clean, and finally the front claws are rubbed 

 over the eyes and top of the head, very much in the 

 way that the common house-fly cleans its head and eyes. 

 A number of genera of Mantidce have a special structure 

 situated on the front femora adapted for cleaning the 

 head and eyes : a little brush of fine hairs occurring in 

 a well-defined patch, which is developed even in the 

 newly hatched young. 



Most of the Mantidce that are coloured and shaped so 

 as to harmonize with their surroundings are very brightly 

 coloured on parts of their body or limbs that are not 

 exposed to view when the insects are in a state of repose. 

 For instance, a species that looks, when still, very like a 

 dead leaf, Deroplatys desiccata, has the inner side of the 

 10 



