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must be heard by the insect which produces them, or by those they are 

 intended to allure. The auditory organ of the grasshopper, however, is 

 not placed in the head, but on the swollen portion of the tibiae of the 

 first pair of legs, each of which has a small cleft on each side of it. 



E. Reproduction. 



Towards the end of summer the females, which, as already mentioned, 

 are recognisable by their long ovipositors, by means of these instru- 

 ments deposit their long, narrow eggs in the earth, where these delicate 

 structures are safer from enemies than they would be if left exposed. 

 The purely protective purpose of this mode of depositing the eggs is 

 shown by the fact that the larva do not remain underground, but leave 

 the soil as soon as they escape from the eggs in the following spring. 

 These larvae resemble their parents in structure and mode of life from 

 the first day of their birth, wings and ovipositors alone being as yet 

 absent. With increasing growth, and after several moultings (see 

 p. 310), these organs also appear, at first as mere rudiments, but after 

 the last moult in their full proportions. 



Thus the larva by degrees passes into the perfect insect without the 

 interposition of a pupal stage. This phenomenon becomes comprehensible 

 when we consider that both larva and pupa lead a similar kind of life, 

 eat the same kind of food, and inhabit the same locality, and if we pay 

 attention to what was observed when we discussed the quiescent pupal 

 condition of lepidopterous insects (see p. 322, Section 4). 



Other Species of Saltatorial Orthoptera. 



The allies of the green grasshopper Family I : Grasshoppers 

 (Locustidae) like the latter, live chiefly in bushes and woods, and wear 

 a green-coloured dress. Those, on the other hand, which frequent 

 meadows, fields, hillsides, and heaths Family 2 : True Locusts 

 (Acrididae) are of gray or brown colour, which protects them as 

 effectively amid their surroundings as the green does their relatives 

 among the leaves. (Compare with frog.) The only parts of the body 

 which are ever of bright colours are the hind-wings, which are covered 

 during rest an interesting point of agreement with lepidopterous 

 insects (see p. 329). The males in this division also are indefatigable 

 musicians, their wing-covers forming the fiddle, and the femurs of the 

 hind-legs, which on their inner side carry a longitudinal row of very 

 fine chitinous teeth, representing the bow. On drawing these teeth 

 along one of the prominent nervures of the wing-covers, the latter are 

 thrown into sonorous vibrations. The organ of hearing is visible on 



