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WOkMS AND ZOOPHYTES. 



THE LEECH 



HA S great reputation for its phlebotomical fervices, being efleemed 

 the beft of blood-letters ; and as fuch known to the ancients. 

 Pliny nannes it the birudo fsnguifuga; was ufed inftead of cupping 

 glafies for perfons of a full habit of body, or gouticaj. There are fevera: 

 forts, all ftrongy allied to worms. In general the body oblong j moves 

 by afluming an arch-like form ; takes its food entirely by fuftion ; 

 and what is very remarkable, has no vifible eje^tory to difcharge it after 

 digeftion ; it is therefore by mofl: naturalifts fuppofed to pafs through the 

 pores of its fkin, perhaps fomewhat in the nature of perfpiration. They 

 have been kept long in glafies without in the lead difcolouring the wa- 

 ter, orcaufing any fediment. Kept 'n glafies they arc good barometers, 

 and predict bad weather by their reftkflhefs and perpetual change of 

 place ; they live long without food, thus kept. They inhabit (landing 

 waters generally, and perhaps by preference, though I have caught them 

 in Ihallow running ftreams. When placed in the middle of fuch a dream, 

 they adhere by fuftion at the tail to whatever they find ; yet often the 

 current is too ftrong for them. In fome places abroad they fwarm fo 

 prodigioufly, as to deter the inhabitants from venturing into many pieces 

 of water; for fuch numbers would attack them, as would drain them 

 quickly of their blood ; by their ftrong adhefion they are difficult to 

 get rid of, and fometimcs leave dangerous wounds, of which circum- 

 ftance there are accounts. 



The Medical Leech has a brown body, marked with fix yellow lines, 

 belly lighter. The Horje Leech has a fiattifh body; in the bottom of 

 the mouth certain great fharp tubercles j is flendereft about the mouth ; 

 thickeft towards the tail ; the tail (lender; belly yellowilh-green ; back 

 dulky. The fea furnifties a kind or two that greatly infeft fifh. That 

 kind ufed medically is faid to faften where a fpot is rubbed with blood or 

 milk, and to difcharge what it has fwallowed, if fprinklcd with fait. In 

 moft particulars conformable to worms, bu£ not capable of propagation 

 by being cut in pieces. 



W O R M S, 



BEING deftitute of feet, trail themfelves along on the ground, 

 and inhabit the earth, or the water ; though they creep along 

 the earth on their bellies, yet their motions are very different from 



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