Altitude or elevation above the sea, has a great influence over a plant's vegetation. The greater that altitude the greater the reduction of temperature, so much so that every feet of altitude are believed to reduce the annual temperature as much as receding a degree from the equator, either to the north or to the south. But this rule is far from universally applicable, for the limit of perpetual snow at the equator is at the height of 15,000 feet, whereas in the 35th degree of north latitude, the limit is at 11,000 feet, being an average of about 120 feet of altitude for every degree of recession from the equator. In the 4.5th degree, the limit is 8,400 feet, being an average of 146 feet for every degree; in the 50th degree, 6,000 feet, or 180 feet for each degree; in the 60th, 3,000 feet, or 200 feet for a degree; and in the 70th, from 1,200 to 2,000 feet, or about the same for each degree as to the 60th degree of latitude. Now I know of no reason why the temperature of elevations below the snow line should not follow the same gradations; and if this be so, these may be taken as a rule.

All plants growing above 7,000 feet under the equator, ought to grow in the open air, in the latitude of London. In general, the same vegetation is produced at the same distance from the snowline in the same latitudes; though, when a place is very near to the pole, a better vegetation is produced in a short period of summer than in places near the snow line under the equator, the plants in the former being there exposed to uninterrupted sunlight.

"At the foot of Mount Ararat, Tour-nefoot met with plants peculiar to Armenia; above these he met with plants which are found also in France; at a still greater height he found himself surrounded with such as grow in Sweden, and at the summit, with such as vegetate in the polar regions. Baron Humboldt, in his Personal Narrative, gives us a similar account of the several zones of vegetation existing in a height of 3,730 yards on the ascent of Mount Teneriffe. The first zone is the region of vines, extending from the shores of the ocean to a height of from 400 to 600 yards, well cultivated, and producing date trees, plantains, olives, vines, and wheat. The second zone is tho region of laurels, extending from about 600 to 1,800 yards, producing many plants with showy flowers, and moss and grass beneath. The third zone is the region of pines, commencing at 1,920 yards, and having a breadth of 850 yards. The fourth zone is the region of Retama, or broom, growing to a height of nine or ten feet, and fed on by wild goats.

The last zone is the region of grasses, scantily covering the heaps of lava, with cryptogamic plants intermixed, and the summit of the mountain bare." - Farmer's Encyclop.

"Of perfect plants, the Daphne Cne-orum seems in Europe to hold the most elevated station, since, on Mont Blanc, it stands at 10,680 feet, and on Mont Perdu at 9,036 feet high. The growth of woody plants ceases on the Alps of central Europe at the height of 5,000 feet; and on the Riesengebirge at 3,800. Oats grow on the southern Alps at 3,300, and on the northern, scarcely at 1,800 feet. The fir grows on Sulitel-ma, in Lapland (68 degrees north latitude), scarcely at the height of 1,200 feet. On the other hand, upon the Alps which divide Italy from France and Switzerland, oaks and birches grow at 3,600; firs at 4,800; and the same plants grow on the Pyrenees above the height of 600 feet. In Mexico, the mountain chains, and in particular the Nevado of Toluca, are covered, above 12,000 feet high, with the occidental pine (Pinus occidentalis), and above 9,000 feet, with the Mexican oak (Quer-cus Mexicana spicata), as also with the alder, of Jorullo (Alnus Jorullensis). On the Andes, palms grow at the height of 3,000 feet. The woody ferns (Cya-thea speciosa, Meniscium arborescens, Aspidium rostratum) are found as high as 6,600 feet; as are also the pepper species, Melastomeae, Cinchonae, Dor-steniae; and some Scitamineae rise to the same elevation.

At the height of 14,760 feet, we still find the wax palms, some Cinchonae, Winters, Escallomae, Espelettiae, Culcitia, Joanneae, Vallea stipularis, Bolax aretioides, and some others." - De Candolle's Philos. of Plants.