298 THE ZOOLOGIST. \ 



" displaying," and it is absurd to suppose that butterflies or other 

 insects can be fascinated or attracted by conspicuous markings 

 or weird postures. I can only conclude that these Mantid " dis* 

 plays " are warning attitudes comparable with the warning 

 " displays " of many lepidopterous larvse (cf. the eye-spots of 

 many species of Chcerocampa amongst the hawk-moths, the black 

 patch in larvse of Dasychira spp. amongst the Lymantriidce, the 

 everted red processes of Papilio larvse, &c). 



Further, I believe that these " displays " have originated from 

 the simple posture of attack or defence into which such a species 

 as Hierodula dyaka throws itself when stimulated by the presence 

 of its prey, or by an enemy's attack. As already stated, that 

 posture — in which the fore legs are drawn up close against the 

 sides of the body, and slightly rotated outwards so as to show 

 their yellow inner aspects — is adopted because it is the most 

 convenient for making a sudden snatch at a moving insect, and 

 it has no other purpose. We may imagine that these uncon- 

 sciously " displayed " parts may become conspicuously marked 

 as in Deroplatys desiccata, that still later these parts become 

 more conspicuous, and the attitude better adapted for showing 

 them off, as in D. shelfordi and Hestiasula sarawaca; finally, 

 that the parts become flower-like, and the " display " a more or 

 less permanent condition in the Mantis's life, as in the Empu- 

 sides.* In other words, the floral simulation of the Empusides is 

 an outcome of a warning " display," which again originated from 

 a simple posture of defence or attack.! These warning " dis- 

 plays," having then been evolved from a simple posture of attack, 

 it is only natural that they should be made under the stimulus 

 of any excitement, such as the presence of prey or an enemy. A 

 Mantis is naturally a ferocious insect, and its first instinct when 

 stimulated is to seize and destroy the exciting cause ; for 

 example, none of the dead-leaf-like species feign death when 



* The Empusides are described by many observers as swaying gently when 

 at rest, apparently to imitate the swaying of a flower in a gentle breeze. This 

 swaying movement is, as shown above, characteristic of the warning display 

 of Hestiasula sarawaca. 



| Dr. Sharp (I. c. p. 177) thinks that the position in which the front legs 

 of Idolum diabolicum is held is very unusual amongst the Mantidce, but I 

 hope that I have shown that this is not the case. 



