Anatomy of the Vine. 133 



satisfy my mind respecting their form and external organisa- 

 tion. Fig. 27. represents one as it is found in the alburnum, 

 consisting of an entire tube; for it will not sepa- 

 rate into the four distinct coils, as the one will 

 readily do when taken from the stalk. The in- 

 ternal surface of these ascending sap-vessels, both 

 in the alburnum and in the stalk of the leaf, have 

 attached to them an innumerable number of short 

 projecting fibres, somewhat like a in Jig. 27. J 

 whether they are absorbents in these tubes, like 

 the lacteals in the animal stomach, or moving 

 mechanical agents, excited into action by the vital 

 principle to propel the sap forward, I do not pre- 

 tend to say. The same kind of vessels will be 

 found in the alburnum of the common cane ( Calamus ruden- 

 tum Lour.), where they are much larger and firmer ; and, with 

 a little trouble, an entire tube may be extracted. 



The part c of Jig. 24. represents the liber of a band. As I 

 described its organisation before, when I referred to Jigs. 3. 

 and 4., I have now very little to say respecting it, except that 

 it is a continuation from the collet, and that these vessels are 

 extremely difficult to be distinguished in the band. Perhaps 

 the readiest way, and one that will prove the most satisfactory, 

 is to cut a stalk through with a sharp razor, as it leaves the 

 smoothest surface, and apply to it the sulphate of iron ; when 

 the vessels of the liber will be discovered by the black preci- 

 pitate upon them, as I mentioned before, from their naturally 

 containing gallic acid. 



The vascular texture is marked d in Jig. 24. : it will be 

 readily found at the back of the liber ; but whether it is sur- 

 rounded in the band by the cellular texture, as it is in the 

 collet, I have not been able to ascertain. By looking on the 

 outside of the stalk of a leaf of a vine, it will readily be dis- 

 tinguished from the cellular texture that lies between the 

 bands, from its being of a darker colour ; and, on removing the 

 cuticle, the vascular texture will be immediately recognised 

 by its fine ligneous hexagonal vessels, which are rather like 

 those at d \njig. 24.; but they are in no wise tubular in the 

 vine, either in the band, or in the bark of the collet. The 

 horizontal view of these vessels in the two bundles at c c in 

 Jig. 4. ought to have been represented hexagonal, instead of 

 round : it was drawn in my early days of investigation. 



Fig. 4. is a tolerably good representation of part of a 

 collet, cut with the assistance of the little regulating machine; 

 hut Jig. 24. has not the most faint resemblance to the ori- 



k 3 



