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PLATE 



II. 



Reprefents the fpiral veflels of a vine-leaf confiderably magnified, copied from Grew, 

 Tab. LL On flowly tearing afunder almoft any tender vegetable flioot or leaf, the 

 fpiral ftrufture of thefe vefTels becomes vifible to the naked eye. They have been cr- 

 roneoufly believed to be air-veflels ; but as they exift equally in the roots of plants, as in 

 their barks, and have no communication with the horizontal perforations of the cuticle 

 of the bark, they cannot be air-vefTels, and are therefore believed to conftitute the ab- 



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forbent veffels of the adult vegetable, and the umbilical ones of the embryon bud. A 

 fimilar plate of the fpiral flrudlure of thefe veflels is given by Duhamel. As they are 

 larger than the vegetable blood-vcflels, and pafs along the whole caudex of each bud 

 from its plumula to its radicle, as well as to the cutaneous abforbents, thofe of the trunks 

 of trees or herbaceous plants may be thought to refemble the rcceptaculum chyli of ani- 

 mal bodies. See Sefk, II. 7. 



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