ORTHOPTERA. 



181 



between the locusts and many of the other grasshoppers of this family. Grass- 

 hoppers feed chiefly on the grasses of different kinds, including most of the 

 cultivated grains ; but locusts leave scarcely anything in the nature of vegetation 

 untouched, when, as often happens, they invade a district where the ordinary 

 herbs and grasses are insufficient to support their vast numbers. Trees and shrubs 

 are then stripped bare of their leaves, and the bark and wood even are not spared. 

 Pressed by hunger, locusts do not refrain from attacking plants which at ordinary 

 times they seem to avoid. They frequently devour their own dead, and even 

 carry their cannibalism so far as to kill and eat the newly-moulted and soft- 

 skinned larvae. Different species of these destructive insects are found in all 

 the great regions of the world ; though North Africa is, perhaps, the one which 



MIGRATORY LOCUST OF SOUTH-EAST EUROPE ( Pachyt ylus migratorius] AND ITS LARVJE (nat. size). 



suffers most from their ravages. The locusts referred to in Scripture belonged in 

 all probability for the most part to the species known as Schistocerca peregrina, 

 which has its chief home in the Sahara and surrounding districts. 



Several other species are found in North Africa, and in South Africa Pachy- 

 tylus migratorioides is one of the most widely distributed. Great swarms of 

 locusts of this species have been seen at different times in recent years ; one which 

 passed over Pretoria in 1891 was estimated to be twenty -five miles long, one and 

 a half broad, and half a mile in depth. It was probably to this species also those 

 locusts belonged, of which Barrow, giving an account of their ravages in the year 

 1797, states that the whole surface of the ground over an area of about two thou- 

 sand square miles was literally covered with them ; and that when driven into the 

 sea by a north-west wind, they formed a bank on the shore three or four feet high 

 and fifty miles long. Amongst European locusts, the best known is P. migratorius,. 



