104 THE OKIGIN OF 



he lias at least the merit of having apprised us that 

 the addition of certain human animal particles, is 

 indispensable to the development of the verminous 

 germ, and for the nourishment of the hatched worm. 

 It is thus that human worms, supported by human 

 nutrition, acquire those differences of structure, 

 which are not noticed in the worms of other ani- 

 mals, though of the same species. 



In this manner may be explained those epidem- 

 ics of verminous complaints, which being ordinarily 

 the effect of uncommon scarcity of food, or of some 

 putrid alteration of the atmosphere, commence with 

 a set of symptoms quite peculiar to a general asthe- 

 nic affection of the highest degree, and of a local 

 consumption of certain parts of the body attacked 

 with it. In fine, it is thus that certain individuals 

 who are well nourished, are exempt from these at- 

 tacks, and in whom the blood consequently circu- 

 lates with force, whose secretions go on with har- 

 mony and regularity, the parts of whose bodies are 

 maintained in a state of perfect cohesion ; in this 

 respect it may be said that health is general and lo- 

 cal. The worms which live at the expense of the 

 human body, thougli of the same species, reproduc- 

 ing themselves elsewhere, v. ill they not be indige- 

 nous to !t?(l6) Do the latter deserve to form a pe- 

 culiar and separate class(17) in the general histo- 

 ry of the worms which the naturalist meets, wheth- 

 er within or without the body of other animals? 



§. LXII. The Taenia canina soli inn, (18) ac- 

 cording to Wci'iifr^ has great resemblance to the 



