300 ORTHOPTERA CHAP. 



become withered and brown. Apparently no live thing was to 

 seen on this hillock except the ubiquitous ants, but after a while 

 he noticed some " lightning-like " movements, which he found were 

 due to specimens of Proscopia. The Insects exactly resemble the 

 withered vegetation amongst which they sit, and when alarmed 

 seek safety with a lengthy and most rapid leap. When attention 

 was thus directed to them he found the Insects were really 

 abundant, and was often able to secure fifty specimens on a single 

 afternoon. These Insects bear a great general resemblance to the 

 Phasmides, but there is no evidence at present to show that the 

 two kinds of Insects live in company, as is the case with so many 

 of the Insects that resemble one another in appearance. Although 

 the linear form and the elongation of the body are common to the 

 stick-Insects and the Proscopides, yet this structure is due to the 

 growth of different parts in the two families. In the Phasmidae 

 the prothorax is small, the mesothorax elongate, while in the 

 Proscopides the reverse is the case. The elongation of the head 

 is very curious in these Insects ; the mouth is not thus brought 

 any nearer to the front, but is placed on the under side of the 

 head, quite close to the thorax. The tribe Tryxalides contains 

 Insects (Fig. 165) that approach the Proscopides in the form of 

 the head and other characters. In most cases the sexes of the 

 Proscopides differ from one another so strongly that it is difficult 

 to recognise them as being of the same species. Usually both 

 sexes are entirely apterous, but the Chilian genus Astroma 

 exhibits a remarkable exception and an almost unique condition 

 of the alar organs, the mesonotum being in each sex entirely 

 destitute of such appendages, while the female has on the meta- 

 notum rudiments of wings which are absent in the male. 



The tribe Tettigides is a very extensive group of small 



Acridiidae, in which the 

 pronotum extends back- 

 wards as a hood and 

 covers the body, the 

 tegmina and wings 



FIG. 179. Tettix bipunctatus. Britain. A, The Insect being more or less modi- 

 magnified ; B, part of the middle of the body ; a, fl g( j j n Qur Jfritish 

 prolongation of pronotum ; b, tegmen ; c, wing. 



species (Fig. 179) this 



condition does not greatly modify the appearance of the Insect, 

 but in many exotic species (Fig. 180) the hood assumes remark- 



