THE TRUE GRAPE-VINES OF THE UNITED STATES. 415 
that this hermaphrodite character of its flowers has been mistaken for a botanical peculiarity, by 
‘which it was to be distinguished, not only from our American grape-vines, but also from the wild 
grapes of the Old World. But plants raised from the seeds of this, as well as of any other true 
grape-vine, generally furnish as many sterile as fertile specimens, while those propagated by layering 
or by cuttings, of course, only continue the individual character of the mother-plant or stock. 
he peculiar disposition of the tendrils in the grape-vines furnishes an important characteristic 
for the distinction of one of our most commonly cultivated species, Vitis Labrusca, its wild and its 
cultivated varieties, from all others. In this species — and it is the only true Vitis exhibiting it — 
the tendrils (or their equivalent, an inflorescence) are found opposite each leaf, and this arrangement 
I designate as continuous tendrils, All the other species known to me exhibit a regular alternation 
of two leaves, each having a tendril opposite it, with a third leaf without such a tendril, and this’ 
arrangement may be named intermittent tendrils.* Like all vegetable characters, this is not an 
absolute one; to observe it well it is necessary to examine well-grown canes, and neither 
sprouts of extraordinary vigor, nor stunted autumnal branchlets. The few lowest leaves of [10 (4)] 
a cane have no opposite tendrils, but after the second or third leaf the regularity in the 
arrangement of the tendrils, as above described, rarely fails to occur. In weak branches we some- 
times find tendrils irregularly placed opposite leaves, or sometimes none at all. 
It is a remarkable fact, connected with this law of vegetation, that most grape-vines bear only 
two inflorescences (consequently two bunches of grapes) upon the same cane, while in the forms 
belonging to Labrusca there are often three, and sometimes, in vigorous shoots, four or five, or rarely 
even more in succession, each opposite a leaf. Whenever in other species, in rare cases, a third or 
fourth inflorescence occurs, there will always be founda barren leaf (without an opposite inflorescence) 
between the second and third bunches. 
Another valuable character, discovered by Prof. Millardet, of Bordeaux, is found in the structure 
of the branches (“ canes,” as they are usually called). These contain a large pith, and this pith is 
transversely separated at each node (point where a leaf Fic. 34. Fis. 35. Fic. 36. Fic. 87. 
is or has been inserted), by what is called a diaphragm. = 
These diaphragms consist of harder, solid pith, of the 
appearance of wood, and are examined best in canes 
6 to 12 months old, when the pith has turned brown 
and the diaphragm is whitish. A longitudinal section 
through the cane will best exhibit them. They are, in 
most species, 1 to 2 lines thick; but in the Riverbank 
grape, Vitis riparia, the diaphragm is not more than 4 
to } line thick ; and in the Sand, or Rock grape, Vitis 
rupestris, it is very little thicker. For us here, the dis- : 
tinction of these species is of no great practical im- | ‘apis.’ Sp pega Oe amma” aad, 
portance; but, as a considerable demand for them has 
sprung up in Europe, it is well to characterize them accurately ; and this character holds good in 
winter, when all others of foliage or fruit have disappeared. There is only one American grape- 
vine, also in other respects an aberrant form, the Southern Muscadine grape, Vitis vulpina, which 
is entirely destitute of such diaph 
The cut represents the diaphragms of different species. Fig. 34, Vitis riparia, with the thinnest, 
and fig. 36, Vitis cordifolia, with a thick diaphragm ; Vites astivalis is similar to this last, and Vitis 
3 Some observations es loose, to be sure) seem to sterile (male) flowers, there is no absolute impossibility in it, 
point to the possibility of the sexual characters of the grape- as we know that ime = lants (willows for example) occasion- 
vines becoming changed under certain circumstances ; and, ally sport in this m 
though I have not seen a case of this kind myself, nor “heard * A vignette representing this form of tendril iets at 
of an instance where fertile vines in cultivation began to bear the end of this paper, but is not reproduced. — Eps 
