284 Facts relative to the Diseases common to 



" Anceps haereo (says the professor) anne et hue re- 

 feram Vermes intestinales hominis, et binas ex Pediculo- 

 rum genere species, praeter ipsum quantum novi in nul- 

 lo alio mammali observatas*." 



Perhaps, this is rather nice. Worms of various spe- 

 cies inhabit the human alimentary canal ; such as spe- 

 cies of Taenia, Ascaris, Trichocephalus, 8cc. I believe 

 that naturalists are by no means acquainted with all the 

 species. Although I have paid much attention to the 

 subject, I confess that I am not prepared to assert, that 

 the same species of worm does ; in any instance, inhabit 

 the intestines of man and of other animals. But no one 

 will be so bold as to assert positively, that this is not the 

 case. 



Some worms are, unquestionably, congenite with 

 the fetal birth. Oilier species seem to be more evi- 

 dently derived from without. In the former case, it 

 were, I think, natural to suppose, that the species of 

 worm is peculiar to the human kind : in the latter, it 

 will, indeed, be remarkable, if the same worm is never 

 found in the body of man, and in that of any other ani- 

 mal. 



I can sav nothing satisfactory concerning the two 

 species of Pediculi, which inhabit the human body. 

 That they are exclusively confined to the human kind, 

 I cannot readily believe. — Is it certain, by the way, 

 that the Pediculus which inhabits the human head in 



- Png. 62. 



