CHAPTER IV 



THE DISSEMINATION OF THE BODY-LOUSE 

 AND LOUSINESS 



Dissemination. A problem which faces every 

 animal and plant is how it shall distribute itself. 

 Each is always seeking new worlds to conquer ; 

 each is to itself the most important thing in 

 creation ; each has the ambition, latent or 

 obviously expressed, to inherit the earth. 

 Except for this tendency to migrate any in- 

 dividual species in a given locality would tend 

 to choke itself out by exhausting the food supply. 

 This is, in fact, going on around us every day. 

 The organisms of a disease enter the human 

 body and multiply enormously till at last their 

 host dies of exhaustion or their poisonous effect, 

 and the parasites die with their host unless the 

 death is merely their means of distribution. It 

 is not the racial ambition of any species to 

 exhaust its food supply, or for the parasite, except 

 in special and exceptional cases, to kill its host, 

 a proceeding which would ultimately lead to its 

 own destruction. Parasitic insects have solved 



