IV 



since carefully re-examined Mantis religlosa, but that he had found both 

 wings and tegmina to be perfectly unmodified ; no rasp was developed on 

 the anterior margin of the tegmina, and no structure that is not to be found 

 in any orthopterous insect could be detected on the inner margin of either 

 pair of wings, the parts said by Goureau to be rubbed. In fact, it is 

 perfectly clear that the sounds which Goureau caused the Mantis to emit 

 were nothing more than such a rustling noise as any Orthopteron can make 

 by shuffling all its organs of flight together, or by the friction of the sides 

 of the abdomen against the posterior inner margins of the wings and 

 tegmina by such a rapid up-and-down movement of the abdomen as should 

 be particularly easy and natural to a member of a group of insects, many 

 of which (e. g.. Mantis, Hierodula, and all the Einjmsidw) habitually carry 

 the abdomen strongly recurved over the thorax throughout their larval life. 

 To enable the insect to bend the body upon itself in this fashion, the first — 

 and sometimes also the second — dorsal segment of the abdomen is peculiarly 

 emarginate. Both dried and alcoholic specimens of immature EmpusidcB 

 are invariably received in this attitude, ^ ^ , and cannot be straightened 

 without breaking the interarticular membranes of the abdominal segments, 

 the dorsal muscles being so strongly contracted and rigid. The attitude 

 probably acts protectively by enabling the insect to diminish the amount of 

 surface visible to an enemy, the short and stout forms and species with a 

 broad exfoliated abdomen (like the Enipusidce) alone assuming it ; the long, 

 slender, and filiform species being apparently already sufficiently well 

 protected by their resemblance to sticks and stalks. It is interesting to 

 find this larval trait continued on into adult life in the South-American 

 Acantlwps, according to De Saussure, whose statement I can corroborate so 

 far as to say that I have always seen dried specimens of the female in the 

 attitude described by him whenever they have been pinned as caught, 

 without any attempt at " setting '" on the part of the captor : — 



" Au repos ces insectes [Acanthops] se donnent par leur posture une 

 ressemblance de plus avec des objets vegetaux. Chez ies femelles la base 

 du ler segment dorsal de I'abdomen est echancree, ce qui permet a I'abdomen 

 de se rejeter en dessus et de prendre une direction verticale ; dans ce mouve- 

 ment il eutraine Ies organes du vol et Ies oblige de se placer a angle droit 

 sur le prothorax ; Ies elytres etant trop etroits pour recouvrir le large 

 abdomen, formant alors avec Ies ailes comme un faisceau de folioles 

 chiffonnees, enveloppant un fruit follicule. Chez Ies males Ies elytres et 

 Ies organes du vol etant plus grands, et ne se rejetant pas en haut, ils 

 derobent entierement I'abdomen, et par leur superposition ils figurent une 

 feuille a bords sinues. La nuance de la couleur feuille-morte varie d"un 

 individu a I'autre comme las feuilles dessechees."=;= 



* ' Mem. Mexiqne,' torn, ii., 1, p. 1-iO. 



