getation, and an elaborate survey of its botanical features would require its subdivision into 20 or more regions characterized by the prevailing vegetable forms; but a mere glance at a few broad geographical divisions must suffice, noticing only the more conspicuous flowering plants. 1. The northern states, east of the Mississippi, from the northern border to Virginia and Kentucky, present a flora essentially European in its general aspects, though it is largely wanting in the alpine and subalpine plants so common in northern Europe. Our alpine or arctic flora (excepting that of Alaska) is confined to the limited areas presented by the tops of the higher mountains of New England and New York; and of the little over 30 species found on these, only 4 are peculiarly American. The trees of this division are largely of European genera; the pine, spruce, birch, oak, maple, ash, elm, and others, which make up the bulk of the forest growth, are also the prevailing genera of Europe, but they are mostly represented here by different species. The principal trees not of European genera are the magnolias, tulip tree, yellowwood, buckeye, locust, honey locust, liquidambar, tupelo, sassafras, and all the hickories; while among the conifers are the arbor vitæ and the hemlock spruce, which by some botanists is placed in a genus distinct from the spruces. Abundant shrubs of European genera are sumachs, thorns, azaleas, rhododendrons, dogwoods, whortleberries, blackberries, &c.; while the laurel (Kalmia), papaw (asimina), prickly ash, witch hazel, spice bush, leatherwood, buffalo berry, and others, are peculiarly American. As in most floras, the compositæ are here very numerous, one eighth of all the species belonging to this family; some of these, as the solidagos, asters, sunflowers, and others, are so abunant as to give a warm coloring to the autumn landscape. Two or three cacti and one pitcher plant, and the mistletoe, genera very abundant in other regions, are found here. A remarkable analogy has been noticed between the flora of the eastern coast of this continent and corresponding portions of eastern Asia, many of the genera of this region being found elsewhere only in Japan, China, and the Himalayas. The flora of this division gradually blends with that of the next. 2. The southern states, from the preceding to the gulf of Mexico, exclusive of southern Florida. Along the mountains northern plants extend far southward. Among southern species of northern genera of trees, the most conspicuous are the great magnolia (M. grandiflora), one of the finest of evergreen trees, the live oak, so valued for timber, and the old-field and long-leaved pines; the pecan, really a hickory, abounds here, and the planer tree, hackberry, persimmon, and holly, not common at the north, have here their centres of greatest abundance; the deciduous or bald cypress, barely a native of the northern region, is here abundant and valuable. Among the trees of genera not found in the northern division are Osage orange, catalpa, wild China, sorrel tree, Georgia bark, devilwood, and alligator pear. Torreya is a very local conifer; and of the four palms, the cabbage palmetto may be ranked as a tree; a grass, the giant cane, often reaches 20 to 30 ft., and forms dense jungles known as canebrakes. The herbaceous plants present great attractions to the botanist, and some from their contrast with northern forms arrest the attention of the unbotanical traveller. Long or Spanish moss is a true epiphyte, and hangs from the trees in such abundance as to form a feature in the scenery; and other tillandsias, several ferns, and two orchids are other epiphytes to be met with in the far south. This region is the home of the pitcher plants (Sarracenia), and of the very local Venus's fly trap (Dionæa), the most wonderful of all carnivorous plants. The bright colors of the coral plant, several species of hibiscus, the Carolina pink (Spigelia), the abundance of phloxes, gerardias, and convolvuluses, and the fragrance of the Carolina jasmine (gelsemium), remind the northerner that he is surrounded by a new flora. 3. Southern Florida, especially the “keys,” presents very distinct features, the trees particularly being those characteristic of the West Indies. Conspicuous among these are the mangrove (also found elsewhere along the gulf), the mahogany and lignum vitæ trees, the poisonous manchineel, several small-fruited figs, the tropical papaw (Carica), calabash, and many others. In the Florida arrowroot or coontie (zamia) is found our only representative of the cycads. The orange grows here as a naturalized plant in such abundance that many regard it as a native. 4. The plains west of the Mississippi, and the Rocky mountains. Immediately west of the Mississippi the flora is not widely different from that on the eastern side; but as the wide plains and the elevated dry plateaus are reached, a different vegetation appears, while that of the Rocky mountains is mainly unlike that of the high eastern peaks; some wide districts have the soil so strongly impregnated with alkali that few plants can exist. The plains are mostly destitute of trees, except along the courses of the streams, where the cottonwoods (species of poplar) are most abundant. Here are found wide areas of single or few species; on the more fertile portions the buffalo grass covers vast tracts, multiplying so freely by its spreading stems that it rarely produces seed. On the sterile portions the “everlasting sage brush” (Artemisia tridentata) gives a sombre hue as far as the eye can reach; the “greasewood” of the travellers (sarcobatus) and other chenopods are often abundant; plants of this family, with a few composites, grasses, and sedges, make up the flora of the wide alkaline stretches. On the more fertile plains the leguminous plants, and those of the phlox and evening primrose families, are frequent. The mountains afford a rich and varied flora; here are found a great va-
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