November to the following rains. The Rice Grasshopper^^ i^gs 

 normally stay in the ground for eight months, but will hatch earlier if 

 kept wet. The degree of moisture and heat have a great influence on 

 this period, and little is yet known of the influence of climatic changes on 

 insect eggs in India. 



Larval Life. 



When the larva is formed inside, the egg breaks and allows it to 

 emerge. There are special devices for securing the rupture of the egg at 

 the right time, which deserve study. Many caterpillars at once eat the 

 eo-o-shell and then start feeding on their food-plant. As a rule, larviB 

 develop rapidly with a plentiful supply of food and proper conditions. 

 The temperature and degree of moisture play a great part in the growth 

 of the young larvae. Feeding is the sole important business, and growth 

 is rapid. Moults occur as necessary; caterpillars shed their skins five 

 times as a rule ; grasshoppers do so five, six or seven times ; the silkworm 

 does so four times. Many bugs do so five times, though the Mealy Bugs 

 and Scale Insects have only two cr three moults. Some aquatic insects 

 moult as many as twenty times. 



Though the process of moulting is necessary to allow of continued 

 growth, it has also a physiological reason. The chitinous matter thrown off 

 is nitrogenous and it is probable that the nitrogenous waste products of the 

 body are eliminated in this manner ; insects have no organs which correspond 

 directly to the kidneys of the higher animals, and a part, if not all, of the 

 nitrogenous waste matter is excreted and periodically shed as chitiu. 



With each moult the form and colour change slightly or greatly. It 

 must not be taken for granted that the number of evident colom- clianges 

 and the number of moults are synonymous. W^e cannot, for instance, 

 collect a great number of the young of a grasshopper, sort them into 

 groups according to size and colour, and then say that each group is the 

 result of one moult ; the changes at one moult may be very slight, though 

 far more striking at every other moult. Moulting is not such a regular 

 automatic process that all individuals of a species have actually the same 

 number, and it has been found that grasshoppers from the same batch of 

 eggs take six, seven or eight moults to attain maturity. 



Larval life may be very short or very long, depending* upon the 

 habits of the insect, as well as on climatic and other conditions. Generally 

 speaking, development is more rapid in hot weather, slower in cold. There 

 is an optimum temperature, the temperature at which development is 

 most natural, which climatic conditions retard or hasten. There is also an 

 optimum degree of humidity, varying for each species. A rise of tem- 

 perature above a certain point or a fall below a certain point may almost 



