182 



INSECTS. 



Tettix subulata (nat. size). 



which occurs chiefly in the south-east, and is found also in Egypt and in West and 

 Central Asia. 



Passing from the locusts, we may briefly notice a few of the other insects of 

 the family. The Tryxalince are remarkable on account of the peculiar shape of 



their head, to which we have already 

 alluded. No species of this sub- 

 family is found in Britain. In the 

 allied Tettigince the pronotum is 

 produced behind into a long process, 

 which in some of the species reaches 

 beyond the tip of the abdomen. Two 

 of the* smallest species of grass- 

 hoppers found in Great Britain belong 

 to the genus Tettix the typical 

 genus of this subfamily. The genus 

 Pneumora, which is represented only 

 in South Africa, is characterised by 

 the bladder -like dilatation of the 

 abdomen in one of the sexes. The hind-legs in this genus are rather short, and 

 are scarcely adapted for leaping. 



stick- and Leaf- The stick- and leaf -insects (Phasmatidce) are chiefly interesting 

 insects. on account of their resemblance to the objects after which they are 

 named. They form one of the families of Cursorial Orthoptera, and, in addition 

 to the easily recognised shape of their bodies, are distinguished by the following 

 characters. The head is distinctly visible from above, and is set somewhat 

 obliquely, with the mouth placed well forwards on the under side. The short 

 prothorax is much shorter, as a rule, than the next segment, or mesothorax. The 

 legs which, in shape, usually harmonise with the shape of the body, are inserted 

 somewhat close to the sides of the thorax, those of each pair being separated from 

 one another by a rather broad sternal plate ; the tarsi are five-jointed, and exhibit 

 a pad-like lobe between the claws of the terminal joint. In the stick-insects the 

 trunk is long, narrow, and cylindrical; the legs are generally long, and, when 

 stretched out unsymmetrically from the body, as they habitually are in the resting 

 insect, look like smaller branches coming off from a thicker, jointed stem. Many 

 stick-insects have no wings at any stage of their life, and it is difficult, in such 

 cases, to distinguish the adult insects from some of the older larvae. In the winged 

 species the fore-wings are usually very short, and often cover only a small part of 

 the hind-pair ; the latter exhibit a division into two distinct areas one more 

 membranous and transparent, and often brightly coloured ; the other, which is 

 narrower, and placed next the anterior border, being coloured like the elytra. 

 When the wings are at rest, the brightly-coloured portion is folded beneath the 

 other part, which alone is then exposed to view, so that there is nothing to detract 

 from the general stick-like appearance of the body. These insects are usually found 

 amongst underwood, or on shrubs and the stems of long grasses. They are mostly 

 inactive during the day, and are not easily seen owing to the way in which their 

 form and colours harmonise with their surroundings. They roam about at night, 



