The structure of the bark is an important distinguishing character for some species; in particular as to whether it peels off and whether in large flakes or in narrow strips or shreds. So, too, the color of the bark is often of taxonomic importance. The form and color of the leaves are often considered, but these characters are variable and may be misleading. The lobing of leaves is a fairly uniform character in most species, some having lobed and others having entire leaves. As to color and texture, the upper surface of the leaf in some species is smooth, glossy and shining and in others rough and dull with varying shades of green. The lower surfaces show similar variations with the addition of varying conditions of pubescence and down or even of cobwebs. In young seedlings the shape and surfaces of the leaves are apt to be quite different from those on the old plants, a character of systematic importance with some species. The flower, as compared with this organ in other genera, is of little importance in distinguishing the species of Vitis, there being an unusual similarity in the structure and appearance of the flowers of the several species. The number of species of Vitis is very uncertain; as, indeed, is their habitat, except that they are generally confined to the temperate or subtropical regions. Some writers give the number as less than fifty but in all territories the number seems to depend on the thoroughness with which the region has been worked over botanically, and also on the judgment of the botanist doing the work. Gray recognized four species as being indigenous to America. Engelmann in his latest publication (_Bushberg Catalogue_, 1883), thirteen, while Munson gives twenty-five. Bailey in _Gray's Synoptical Flora_, gives twenty-three species. Planchon (in 1887) gives twenty-eight species for the world. Seventeen of these are credited to America, ten to Asia, and one, the Vinifera, of unknown nativity. All of these lists, however, are known to be incomplete. Bessey[124] says that the grape is not native to the southern hemisphere, and Planchon credits none to any section south of the equator. Bailey credits two to Australia in a work not intended to cover more than those of American interest. And a correspondent[125] from that continent writes us giving a list of nineteen named and botanically described species indigenous to Australia. The number of species of grapes in the world depends upon the arbitrary limits set for a species and our knowledge of the genus is yet too meager to set these limits with certainty. SPECIES OF AMERICAN GRAPES. CONSPECTUS OF NORTH AMERICAN SPECIES OF VITIS. A. Skin of mature berry separating freely from the pulp. B. Nodes without diaphragms; tendrils simple =1. V. rotundifolia.= =2. V. munsoniana.= B.B. Nodes with diaphragms; tendrils forked.