Metamorphoses of Insects. 1 2 1 



body against another, and such have usually a special 

 hearing organ which in crickets and locusts is placed 

 under the knee on the outside of the foremost pair of 

 limbs. 



Development and Metamorphoses. Insects' eggs have 

 often a sculptured shell (fig. 6), and are laid in such 

 places as are suitable for the supply of food to the 

 newly hatched larvae. For this egg-laying the parent 

 has often an organ formed of the modified appendages 

 of the abdomen or of the post-abdomen. These 

 organs are in the form of bristles, pincers, or saws, 

 and by these the insect prepares the place for and de- 

 posits its eggs ; hence, the organ is called an ovipositor. 

 The young of most insects emerge from the eggs 

 as worm-like animals called caterpillars or larvae. 

 Each of these is a little jointed creature, having a head 

 which bears eyes and a pair of antennae. Its mouth is 

 armed with strong jaws, and the surface is often covered 

 with bristles. Each of the three anterior segments of 

 the body of a caterpillar is usually provided with a pair 

 of little stumpy feet, and sometimes, as in the larvae 

 of butterflies and saw-flies, the hindmost joints have 

 also foot-like processes. Caterpillars are very voracious 

 in their habits and grow rapidly, frequently moulting 

 or shedding their skin. On reaching the limit of 

 size, many caterpillars begin to spin for themselves 

 a case or cocoon. The glands from which this pro- 

 ceeds are two long tubes placed in the abdomen, but 

 opening on the lip, and the material of the cocoon 

 is silk. Those that have no such labial glands also 

 give up eating, and their skin thickening they become 

 fixed and rigid and are known as pupae, or from 



