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Microscopical Essays. 



times feen ; all the larger eels have this appendage, which alfo 

 bears the marks of having been burft. Now as the younger eels 

 have not this appendage, nor any markb ot a rupture, we may 

 reafonably conclude that it is from hence that the little eels iffue 

 from the parent. 



In the latter part of the year, and during the winter, thefe eels, 

 are oviparous, and the young eels may be feen to proceed from 

 the egg ; at other times they are viviparous, fix live eels have 

 been feen at one time in the belly of the parent, twenty- two eggs 

 have been counted in the ovary. M. Muller fufpefted that there 

 was a difference of fex in fome of thefe animalcula, but it was 

 left to M. Roffredi to afford the proof, and it was only from 

 a variety of repeated obfervations that he could allow himfelf 

 to be convinced of this truth. He continued his refearches upon 

 the fame fubjecl: on other microfcopic eels, and has fmce been 

 able to difUnguifh the fexual parts of the vinegar eels. ■ 



The next eel we fhall defcribe is the eel of vinegar, Fig, f„ 

 and that becaufe it is oviparous and viviparous ; like the pre- 

 ceding it is filiform, but in other refpects they differ confiderably. 

 It is longer, not near fo large, the tail is fmaller, and more 

 tapering than that of thepafte eel; it moves with much greater 

 eafe, and is more lively. We may obferve in fmall, at the tail of 

 this eel, what may be feen at large at the beginning of the viper's 

 tail, a little kind of tongue ab, which fometimes adheres to the 

 fkin, at other times is feparated from it. An alimentary duel: may 

 be eafily difcovered, but no other inteftines can be difcerned* 

 without deranging altogether the organization of the animalculum. 



The 



