94 ANIMAL PARASITES AND MESSMATES. 



There are some which, like leeches, seek assistance 

 from their neighbours, but are content to snatch their 

 food as they pass, and only attach themselves for a 

 short time to the host which they despoil ; they retain 

 their fishing or hunting tackle, as well as their organs of 

 locomotion. These parasites, which never take up their 

 lodging on the host which nourishes them, have no 

 sooner sucked his blood, or devoured his flesh, than they 

 resume their independent life. 



They do not disfigure themselves, nor put on any 

 special costume, like those which seek a permanent 

 abode. Gluttony is not with them the only moving 

 principle of existence ; they do not forget what they owe 

 to the world, and keex3 up an appearance which allows 

 them at all times to present themselves afresh. 



Parasites are scattered over every region of the 

 globe; they choose their place, and observe, like all 

 living creatures, the laws of geographical distribution. 

 All do not inhabit the animal kingdom ; some seek for 

 assistance in vegetable life. Many insects lay their eggs 

 in seeds or fruits, and their progeny, as soon as they 

 are hatched, find abundant nourishment in the sap or 

 in the farina stored up for the young plant ; others 

 pass into a state of lethargy while the seed is dry, 

 and recover their activity every time that they receive a 

 little humidity. 



The female of a coleopterous insect deposits its eggs 

 in the nut, and in proportion as this grows, the young 

 larva devours the kernel. When it is brought to table, 

 it encloses only the skin and the excretions of the larva. 

 A weevil establishes itself in a similar manner in cereal 

 plants, and, small as it is, it may produce g':eat calamity 



