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XX VIII.—On the Shedding of Branches and Leaves in Conifere. 
By Dr James Stark of Huntfield. (Plate XLIV.) 
(Read 3d January 1876.) 
In referring to the tendency to bilateral ramification on the branches and 
even on the main stem in Cupressinez, such as Cupressus, Thuja, and Libocedrus, 
Professor Sacus, in his Text-book (Bennett’s translation pp. 444-5), thus 
expresses himself: ‘‘Branch systems of three or four orders of shoots are 
developed in one plane in such a manner that a system of this kind assumes a 
definite contour, and somewhat the appearance of a pinnate leaf. In Taxodium 
the foliage-leaves are formed in two rows on slender branches a few inches in 
length; in 7. distichum these fall off in autumn, together with their leaves, thus 
presenting a still greater resemblance to pinnate leaves.” 
The shedding of leafy twigs (or cladoptosis, as it has been termed) in various 
Cupressineze is not unknown to botanists, and the passage above quoted is 
sufficient to show that the analogy, in behaviour, of such twigs to leaves, has not. 
been overlooked. Indeed, this singular phenomenon is one of the most striking 
cases of one morphological structure (the shoot) behaving physiologically like 
another, and wholly distinct one (the leaf). 
Although the subject of this paper is not to be regarded as a new one, yet 
it does not appear to have attracted the attention which its importance merits; 
and hence I venture to believe that in laying a few observations and experiments 
before the Society, my work may not be considered superfluous. 
My attention was specially directed to this subject by an incident which 
happened a few years ago. The spring frosts in May blighted three of the 
branches of a fine Nootka-Sound cypress which stood on the lawn in front of 
my house. In the hope that these blighted branches would partially recover, 
they were not removed that year; but as they died up to the stem, I resolved 
to cut them off the next spring. As all are aware, the branches of this cypress 
have strong buttresses of bark at their junction with the main stem, as if to aid 
in supporting the branch. When the knife, however, was applied close to the 
stem, to my surprise it passed through the bark without resistance, and I had 
only to cut through the thin quill of woody fibres when the branch dropped 
into my hands. 
On examining the place from which it had been removed, it was found that 
the bark of the tree under the part where the branch had adhered was wholly 
cicatrised, so that the branch had only been adhering by its quill of woody fibre; 
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