Zoology.-] NATURAL HISTORY OF VICTORIA. [Insects. 



legs not being thickened for leaping, from the saltatory Grass- 

 hoppers and Locusts (Locustidoe), the Crickets (Achetidce) and 

 GryllidoB. 



They are confined to warm latitudes ; the Indian Archipelago 

 being their great centre. They are all harmless, plant-eating 

 creatures. The males are smaller, and with longer and more 

 slender legs and antennae than the females. In some the males 

 have large wings, and the females only imperfectly developed ones 

 or none, while in others both sexes have fully- developed wings, 

 and in many others the adults of both sexes are apterous. The 

 legs when lost are gradually restored in successive moults ; but 

 these renewed legs are generally smaller than before, and may be 

 recognised by this difference from the corresponding one on the 

 other side. The relative proportion of different parts of the legs 

 and parts of the thorax afford specific characters ; and the three 

 terminal segments of the abdomen containing genital parts are also 

 used for discriminating species. In the male the three last joints 

 on the ventral side are smaller than the rest, and swollen ; in the 

 females the 7th on the under side forms a boat-shaped ovipositor or 

 operculum protecting the genital appendages of the two terminal 

 joints, sometimes forming long, exserted styles or plates. In both 

 sexes the under-side of the ninth dorsal segment has two, generally 

 filiform, very short, setose styles, greatly developed in the 

 Australian species into two long flattend appendages. The relative 

 size of the two divisions of the metathorax above affords specific 

 characters. 



The family Phasmidce is divided into the following sections, 

 which are only temporary, as Bacillce of the 1st may hereafter be 

 found to have winged males. A difficulty also arises in the 

 immature stages of development of the tegmina and wings of 

 species, having them large when adult. The texture sometimes 

 enabling one to distinguish small wings in adults, from immature 

 small stage of large-winged species. The main vein of the costal 

 area of the wing is simple in the male and forked in the female, 

 or forked in both sexes. The ocelli are not even of sexual import- 

 ance, some individuals having three, and others of the same sex and 

 species not having any. 



[ 34 ] 



