172 



INVERTEBRATE ANIMALS. 



as the Locusts and Grasshoppers, have the hindmost pair of legs 

 much longer than the others, giving them a considerable power of 



leaping. All the Orthop- 

 tera are extremely vor- 

 acious, and every one is 

 acquainted with the ter- 

 rible ravages occasionally 

 caused in hot countries 

 by swarms of locusts. 



The most destructive 

 species is the Migratory 

 Locust ( CEdipoda migra- 

 toria), which is very 

 abundant in Africa, 

 India, and throughout 

 the whole of the East. 

 Owing to the rapidity 

 with which they devour 

 everything they can pos- 

 sibly eat, and owing to 

 their enormous numbers, 

 the Locusts are compelled 

 to be constantly on the 

 move, looking for " fresh fields and pastures new." It is from these 

 migrations in vast bodies in search of food that the Migratory Locust 



Fig. 117. — Different stages in the metamorphosis of 

 a Grasshopper. A, Larva; B, Pupa, with the rudi- 

 mentary wings ; C, Adult or imago, with the fully 

 developed wings. 



Fig. lis. — Orthoplera. The common Cockroach (Blatia orientaluf), 

 male and female. 



takes its name. When one of these destructive hosts visits a district, 

 it only needs a few hours to convert the most fertile country into a 

 howling wilderness. In an incredibly short space of time eveiy green 



