THE DEVIL'S RIDING-HORSE (MANTID&). 25 



exist in the state of stumps, under the form they assume 

 during the nymph period. But whilst among mantidse, 

 in the case of the non-separation of the organs of flight, 

 it is always the nymph state that persists, among 

 Phasmidae, on the contrary, the larva state is that which is 

 preserved most often : in the last-mentioned Orthoptera, 

 when the wings are wanting, they are entirely obliterated. 

 The development of the mantidae, then, is arrested at a 

 later stage, a fact indicating a more advanced step in 

 transformation, and a nature more perfect. 



Protective and Aggressive Resemblance. 



A most interesting feature of the mantidae is their 

 presentment, in a high degree, of a phenomenon which 

 indeed the whole order Orthoptera presents that of 

 adaptation to their conditions of life. In a more or less 

 wonderful manner, their appearance harmonizes with 

 their surroundings, with the soil or vegetation on which 

 they live, tending to their concealment, and so escape 

 from enemies, when the resemblance is protective ; and 

 the same circumstance is of special value in enabling 

 them to lie in wait for, and to creep upon their prey, in 

 which cases the resemblance is aggressive. This one 

 character that of adaptation leading to concealment, 

 then is of use to its possessors for two different ends, 

 for defence and for attack. 



