Anatomy of the Vine. 23 



each other at the back of the joint. The vessels which com- 

 pose them proceed from upwards of twenty divisions; they 

 form a circle just within the edge of the stem, and within that 

 circle another is formed belonging to the next leaf above, and 

 within the second are those of the third, &c. Every person 

 interested in this subject I would recommend to examine one 

 of the rhubarb stalks under such circumstances. 



That the bundles of the vascular texture ofjg. 2., which 

 lie on the outside of the six divisions, and commence at n o p 

 •qrs, and join their respective claws above, may be easily distin- 

 guished, their cuticle and cellular texture are injg. 2. removed 

 from them, as well as from the others below the joint, that 

 their general arrangement so far might be seen at one view. 



I wish now to draw your attention particularly to those six 

 sets of vessels of the claws e J g li i k, Jig. 2., which are a 

 continuation from the six divisions of the collets to the base of 

 the stalk of the leaf. The first layer consists of the cuticle ; 

 the second of the cellular texture; the third of the vascular 

 texture, similar to Jig. 3. at g g above z ; the fourth of the 

 liber at J J above z ; the fifth of the ascending sap-vessels of 

 b c d e above z ; and the sixth of the spiral vessels Jat a 

 above z ; so that we see by this admirable arrangement the 

 special protection given to the spiral vessels : for they are those 

 which convey the secreted juice from the matured liber to the 

 young extending shoot, previously to the formation of the 

 ascending sap-vessels of the alburnum. The vessels of the 

 medulla are not continued in so distinct a manner as the others, 

 they are formed in the stalk and leaf from the cellular texture 

 of the second layer. No part of the ligneous fibres of the 

 concentric layer of the collet enters into them, for the reasons 

 already given. As the whole of those vessels of the claws are 

 so peculiarly interesting, I shall exhibit them in a future 

 drawing, with further particulars respecting them. 



I have been rather short in my description of the liber, con- 

 sidering its great importance to the plant, because the vessels 

 of the vascular texture, which are in bundles, are much more 

 conspicuous, and these two always act in unison together. 

 Some writers*have called the whole of the bark the descending 

 vessels ; but I consider only those of the liber and the cellular 

 texture to be permanently so in the vine, as I hope fully to 

 explain when I describe the second year's growth of the shoot 



I flatter myself the ascending sap has been satisfactorily 

 shown to pass up the vessels of the alburnum into the leaf, but 

 no proof has yet been given that it proceeds any farther. To 

 prove it, I shall avail myself of the gallic acid, which exists in 



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