COCKROACHES, ETC. 135 



Mantis, and there seems every reason to suppose that 

 they are sufficiently deluded by the floral simulation 

 of their enemy to approach within striking distance. 

 When the Mantis is irritated the " raptorial limbs, which 

 are usually held folded together in front of the pro- 

 thoracic disc, are now widely separated until they lie 

 in the plane of the disc, the inner aspect of the 

 coxae being directed forwards ; the femora and tibia 

 remain folded upon them as before. It is now seen that 

 the internal aspect of the coxae is coloured a brilliant 

 purple, dotted over with circular white or pale blue 

 spots, and the femora have a warm red-brown colora- 

 tion on this aspect" [p. 128]. This attitude is the same 

 as that adopted by Hierodula when ready to seize prey, 

 but in addition the abdomen is greatly distended, and 

 in immature examples is curled up ; the intersegmental 

 membranes at the base of the abdomen are bright 

 purple in colour, whilst on those at the hind part of 

 the abdomen are black eye-spots. In this attitude 

 the insect presents a terrifying appearance, which, in 

 Captain Williams's opinion, would deter even a large 

 Lizard from seizing it. This species is of great interest, 

 as showing an intermediate stage between such a form 

 as Hestiasula and that which will be next considered. 

 It displays its warning signals when irritated by ex- 

 posing to view the inner sides of the front legs which 

 normally are concealed, but the under side of the pro- 

 thorax, which in Hestiasula is part and parcel of the 

 whole scheme of warning coloration in that insect's 

 display, is in Gongylus wonderfully coloured to resemble 

 a flower, and is displayed all the time that the insect 

 is at rest and waiting for its prey. This is an instance 

 of alteration of habit and colouring to meet the ever- 



