OF THE HIBIAN BODY. 55 



The transverse fibres are connected together by 

 means of an abundant cellular tissue, which being 

 moistened is greatly relaxed, and lengthens the 

 body very cousiderably. Goeze asserts, that a 

 piece of this worm one line long, after being mace- 

 rated, acquired the length of an arm. What an 

 extraordinary length may not this worm attain in 

 the living human body ! 



§ XLY. It is to be remarked, that the external 

 structure of the head and tail of the lumbricoides, 

 is peculiar. 



If we observe the head with the naked eye, 

 we see three beautiful hemispherical eminen- 

 ces,(20l) which insensibly terminate in a very 

 sharp point. 



Under the microscope we perceive that these 

 three eminences are perfectly hemispherical, 205) 

 and that Vallisneri described them with accuracy, 

 when he compared them to three small hills. (^03) 



To a triangular aperture in the centre of these 

 eminences, Pallas has given the name of a mouth 

 with three lips, trilabiata, 



AYe cannot perceive all these appearances in 

 the dead worm, because every part of the body is 

 then relaxed. In the living lumbricoides, these 

 three hemispherical eminences change their aspect 

 as Goeze informs us, (204) who had the good lor- 

 tune to see one of these worms at the instant it was 

 sucking. In the living worm, on the contrary, we 

 see that these three hemispherical protuberances 

 are pyramidal, with a convex base truncated cxte- 



