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Updated: June 29, 2025
When we add to these several points of identity the fact that the petiole of Solanum jasminoides, after it has clasped a support, assumes one of the most characteristic features of the axis, namely, a closed ring of woody vessels, we can hardly avoid asking, whether the difference between foliar and axial organs can be of so fundamental a nature as is generally supposed?
All the specimens have a green blade which, in ordinary speech, we call the leaf. Some have a stalk, or petiole, others are joined directly to the stem. In some of them, as a rose-leaf, for instance, there are two appendages at the base of the petiole, called stipules. These three parts are all that any leaf has, and a leaf that has them all is complete. Let us examine the blade.
A clump of pussy willows bears many queer-shaped clusters which the entomologist calls pine cone galls; in the center of each one a larva dwells in his silken case. On the red oaks over head are other galls, the oak apples. The buttonbush has the ash-colored cocoon of the giant silkworm, made out of a rolled leaf, the petiole of which is fastened to the branch with silk.
The pupils have described the folding of the leaves in some of their specimens. In the Beech, the leaf is plicate, or plaited on the veins. In the Elm, Magnolia, and Tulip-tree, it is conduplicate, that is, folded on the midrib with the inner face within. In the Tulip-tree, it is also inflexed, the blade bent forwards on the petiole.
Very soon afterwards it disarticulates itself from the petiole, and drops off like a leaf in autumn. I have seen this process of disarticulation in no other tendrils, for these, when they fail to catch an object, merely wither away. Bignonia venusta. The tendrils differ considerably from those of the previous species.
The attitude assumed by the stem after the petiole had clasped the stick, was that of a man standing by a column, who throws his arm horizontally round it. With respect to the stem's power of twining, some remarks will be made under C. calycina. Clematis Sieboldi. A shoot made three revolutions against the sun at an average rate of 3 hrs. 11 m.
Tendrils, which have caught nothing, ultimately contract into an irregular spire, as they likewise do, only much more quickly, after clasping a support. In both cases the main petiole bearing the leaflets, which is at first straight and inclined a little upwards, moves downwards, with the middle part bent abruptly into a right angle; but this is seen in E. miniatus more plainly than in E. scaber.
The Shat lon is a production of Shrub which I have taken heretofore to be a Species of Loral and mentioned as abounding in this neighbourhood, and that the Elk feed much on its leaves. it generally rises to the hight of 3 feet, and not unusially attain to that of 5 feet. it grows very thick and is from the size of that of a goose quil to that of a mans thumb, Celendric. the bark of the older or larger part of the Stalk is of a redish brown Colour, whilst that of the younger branches & succulent Shoots are red where most exposed to the Sun and green elsewhere. the Stem is Simple branching, reclineing and partially fuxouse, or at least the Smaller Stalks or Such parts of them and their boughs which produce the leaves, take a different direction at the insertion of every petiole.
Dutrochet asserts that the petioles of the leaves spontaneously revolve, as well as the young internodes and tendrils; but he does not say that he secured the internodes; when this was done, I could never detect any movement in the petiole, except to and from the light.
Tendrils which have caught nothing simply bend downwards and inwards, like the extremities of the leaves of the Corydalis claviculata. But in all cases the petiole after a time is angularly and abruptly bent downwards like that of Eccremocarpus.
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