DEVELOPMENT OF THE GRASSHOPPER 15 



be to protect the delicate young hopper while it is forcing 

 its way up through the soil. The newly- hatched grass- 

 hopper is almost pure white in colour. The colour, however, 

 gradually changes so that within a few hours it has be- 

 come dark yellowish brown. 



Developmeiif of the grasshopper. — All insects during 

 their growth go through various stages or instars. This 

 is made necessary from the fact that the outer covering 

 of the body becomes ver}- hard and inelastic. In this 

 condition, it does not allow the insect to increase in size 

 to any very marked extent. In order to allow for a 

 comparatively free increase in size, it is necessary that a 

 fresh, soft and elastic covering or skin should be formed 

 beneath the old one and that the old one should be shed. 

 This fresh covering, in its turn, becomes, in time, hard and 

 inelastic and has later to be replaced by another one 

 formed underneath it. 



In the case of grasshoppers, this process of moulting 

 takes place at intervals during the whole period of growth 

 up to the time when the insect becomes full-grown. 

 The growing period is thus divided into a series of stages 

 or instars which are niarked off from each other by the 

 various moults. The first stage or instar, therefore, extends 

 from the time the young grasshopper hatches to the time 

 when the hardened outer covering is shed for the first 

 time. 



The newly-hatched Rice Grasshopper resembles, in 

 general appearance, the full-grown insect. We find jaws, 

 eyes and legs present very like those of the adult insect. 

 There is, however, as j^et no sign of wings. The colour and 

 markings on the body are also very different from those of 

 the full-grown insect, while the antennae are also distinct- 

 ly simpler in structure. 



FIRST INSTAR. (PLATE 1, FIG. 2.) 



The accompanying figure gives an accurate representation of the 

 insect during this first instar after it has assumed its permanent colour. 

 The following are the chief points to he noted : — 



Length of hody on hatching ... ... 5 — 6 mm. 



Length of antennas ... ... 2 „ 



Numher of segments or divisions in antennae ... 13 

 The 8th segment shows signs of division. 

 The antenna is slightly cluh-shaped (clavate), the distal six 



