STEM, LEAVES, AND BUDS. 
33 
of the buds. The former says (El. Phil. Bot., Ed. ii. 261), 
it may be seen with the naked eye, that a layer of wood issues 
from the bud into the branch beneath, and attaches itself 
to the wood, and on using the magnifying glass, young spiral 
vessels, &c., &c., may even be perceived to penetrate into 
the branch.” If the author had taken the trouble to read 
the sentence, he would have seen, that I certainly said, That 
vessels with a cellular tissue issue from the bud downwards 
into the branch,” but by no means, that the entire new layer 
of wood was formed by it, but that the latter also grows to it 
from the sides, so that the vessels, as it were, inoculate one 
another. The manner in which this is done, I have not only 
elaborately described, but also representd in the seventh table 
of the Icon. Anat. Bot. part i. table 7, fig. 6-12. He recurs 
to my former opinion in page 111, and carefully states who 
has confuted it. He then adds, p. 112, — “ Link has latterly 
changed his views on this point, and he pronounces the spiral 
vessels, in the vicinity of the pith, to be unchangeable, as 
Mirbel and others have shown. He gives ‘ the alder ’ as an 
instance, which exhibits, after forty years, the same vessels 
that it had at first.” This is all that he says of my represen- 
tation, and he has thus shockingly mutilated it. He also says, 
p. 121, — “ Link places the cambium layers with the liber, and 
calls them ‘ internal liber.’” The sentence referred to treats 
of the sap, which I certainly distinguish from the cambium. 
But this shall not influence my analysis of what follows. 
The third division treats of the structure and the growth of 
the Aloinece. He commences with these, because they have 
the greatest similarity in their structure with the Dicotyledons, 
as the stem consists of bark, wood, and pith. The author 
draws the following inferences from his researches upon the 
Draccena ferrea : — 1st, A homogenous tissue, which belongs 
to the cellular system, and which is distinguished by the cir- 
cumstance of its extended cells carrying a more or less cloudy 
coloured juice, is the original basis of the vascular or woody 
bundles. 2d, The development of the vascular or woody bun- 
dles, considering it in its whole course, does not take place 
in an uniform manner, but portions of it are capable of being 
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