DISTRIBUTION OF PLANTS IN ZONES. 671 



different parts of the globe differ a good deal in their vegetation, and 

 we may therefore enter into rather more detail here. 



In the Mediterranean region evergreen dicotyledonous trees with glossy 

 leaves, showy shrubs, and many bright-coloured bulbous plants abound ; 

 Erica arborea, the Bay, and the Myrtle are characteristic ; the Turkey, 

 Holm, and Cork Oaks, the Chestnut, the Strawberry-toee, with the 

 Cherry-Laurel, Laurustinus, and Pomegranate are frequent, as are also 

 the Phillyrese, Rosemary, Oleander, &c. 



The Vine is a native of this zone, and is said to attain a diameter of 

 3 to 6 inches, and to climb to the top of the highest trees in the forests 

 of Mingrelia and Imeritia. The barren tableland of Asia falls in this 

 zone, as does Japan, which has a rich vegetation. In America are found 

 abundance of Oaks and Pines, Maguoliaceae (such as the Tulip-tree), a 

 number of Leguminous trees, with thorny Smilax-shrubs and gigantic 

 Reeds; the Gleditschise on the banks of the Ohio are evergreen, with 

 climbing Bignoniae ; evergreen trees here correspond to those of Southern 

 Europe, intermingled in the forests with Oaks, Beeches, Ash, and Pla- 

 tanus occidentalis. 



In the southern hemisphere this zone includes part of New Zealand and 

 Australia, where, again, evergreen trees are intermixed with forest-trees 

 with deciduous leaves j shrubby Ferns abound, and the Leguminosae and 

 Myrtaceae are well represented. 



In South America, the Pampas-plains of Buenos Ayres fall in this zone, 

 especially characterized by arborescent Grasses. Southern Chili represents 

 the warm temperate vegetation with its evergreen forests of Myrtacese, 

 Beeches, and Araucarias j the Fuchsia is also characteristic of this region. 

 The Chilian Palm, like the dwarf Palm of Southern Europe and the 

 Palmetto of North America, forms an outlier from the subtropical region. 



5. The Cooler Temperate Zones. Equatorial boundaries, the annual 

 isotherms of 54'5 F. (12 C.) ; polar boundaries, the isotherms of 41 F. 

 (o C.). The especial characteristics of these zones are the forests of deci- 

 duous trees with inconspicuous blossoms, intermingled with social Conifers, 

 together with the Grass-pastures. Here the trunks of the trees are over- 

 grown only with Mosses and Lichens ; the Honeysuckle, the Ivy, and the 

 Hop are the only important climbers, very different from the Lianes of the 

 tropics. Shrubs are pretty frequent, but they mostly lose their leaves in 

 winter, such as Roses, Brambles, Viburna, &c. The* social Dwarf-grasses 

 on good soil, with the Sedges, Cotton-grasses, and Mosses of wet ground, 

 characterize the plains, and extensive Heaths prevail in some districts. 

 The contrast between summer and winter is strongly marked in the Aspect 

 of vegetable life : the trees are stripped of their leaves, the herbs die 

 down to dwarf tufts, or hide themselves altogether in the ground, and 

 the snow covers the surface of the plains in severe weather ; but the 

 warmth of summer, which brings out a lively and varied show of flowers, 

 is sufficiently high to ripen the seeds of many, and thus annuals are more 

 numerous than they are further north. 



This zone is not represented in Africa or in the South Sea. In South 

 America it includes Patagonia. 



6. The Subarctic Zone. Equatorial boundary, the annual isothermal 

 line of 41 F. (5 C.) ; polar boundary, the isotherm of 36 0> 5 F. (2 C.) 



