VOL. XIII.] PHILOSOPHICAL TRANSACTIONS. dQQ 



agreeable to me, and to be the true use of this part we call the head, is this: 

 that by means of these hooks and spikes it might fasten itself, and so prevent 

 its too easy ejection out of the body. For it being so very long and large too, 

 and its body in many places winding, and convoluted, the descent of the faeces 

 upon all occasions would be apt to carry it out with them, had it not this hold, 

 which is so fast, that rather than loosen itself, parts of the body are sooner 

 broken off, which we frequently see in the stool. When it penetrates the coat 

 of the intestine, it contracts its hooks in, and draws up its head to a point, 

 then expands them, and takes firm hold of the membrane, by darting its several 

 poniards into it, which excites those intolerable pains which those that are 

 troubled with them so much complain of; that I have known it to that extre- 

 mity, that some have been scarcely dissuaded from offering violence to them- 

 selves, to free themselves, as they thought, from a great misery ; and hence it 

 is, that this worm is of so difficult a cure, that though by medicines and purges 

 vast quantities at times may be brought away, yet some can hardly get a perfect 

 cure all their life time, as I know of one who for above 20 years has been af- 

 flicted with it. 



I have already observed the orifices in every joint to be of 2 sorts ; that in 

 several worms, both from human bodies, as also in those of brute animals, 

 they are placed much about the middle of the joints on the edges, most fre- 

 quently alternately, in one joint on the right hand, in the other on the left, 

 sometimes in two, seldom in more on the same side; they are protuberant, 

 something like a papilla, (fig. 7) and in the middle a foramen easily enough to 

 be perceived by the naked eye, and will readily admit a hog's bristle. In the 

 other sort, these protuberances are placed about the middle of the flat of the 

 worm, towards the upper part of the joint. At present I shall chiefly insist 

 upon the former sort, which has occurred most commonly to me, and a short 

 black line here, placed transverse to the body, I think was the first that gave 

 me notice of them ; though since in others I have not so constantly seen it, 

 but only a protuberant orifice about the middle of the edges of the joints. 

 That they are so many mouths, I shall argue, first, from the. great quantity of 

 chyle they are often turgid with. Secondly, from the great appetite, but more 

 often thirst, but almost always that emaciation which they occasion. Thirdly, 

 that there is no other mouth besides observed. Fourthly, that no uses can so 

 fitly be assigned to these orifices as their being mouths. 



As to the first, all that have observed them, cannot but confess that they are 

 often very turgid ; as that I have by me 8 yards long, at first did very plainly 

 appear; and having put it into spirit of wine, I found after a little while it had 

 muddied it, by spewing out a large quantity of a chylous juice, which made a 



