7. Zones of the Central and Southern Parts of North America.

Mixed and deciduous forests. Mixed and deciduous forests are found south of the coniferous forests. They do not cut across the continent from west to east, but grow in the western part only where the climate is wetter. From there they spread south, almost reaching the Gulf of Mexico.

Compared with the deciduous forests of Europe, those of North America are more varied. This is especially noticeable in autumn, when the leaves are bright and many-coloured. The chief trees are oak, beech and chestnut, but of different species than in Europe. There are trees that are not to be found in European forests: sugar maple and tulip-trees.

The magnolia is very common in the south. It is usually found entwined with climbers and wild vines.

Most of the mixed and deciduous forests have been felled, and hardly any measures are taken to replant them.

Prairies. West of the mixed and deciduous forests the climate becomes drier, and instead of forests there is chiefly grass. The steppes of North America are called prairies. They are covered with tall, thick grass, including feather-grass and others. Closer to the Cordilleras the rainfall is still lower and the vegetation poorer. Here and there grow tufts of low grass.

Today the prairies are almost entirely tinder cultivation. The only animals that are more or less plentiful are small rodents.

The soil is very fertile. Much wheat and corn is grown.

Deserts and Semideserts. The plateaus between the Cordillera ranges are desert and semidesert regions. In California they extend to the very Pacific. Only wormwood and prickly scrubs grow there.

Peculiar to Mexico are the cactus and agave. These plants are adapted to the dry climate. They have thorns or spines instead of leaves, and their green, fleshy stems are stores of moisture. Side by side with cacti grow agaves. These consist of bunches of fleshy, sap-laden leaves on tall stalks.

The semideserts and deserts are thinly inhabited. The chief occupations are sheep-breeding and mining.

Subtropical and Tropical Regions. In the Gulf of Mexico coast-lands and in Florida the vegetation is of the wet tropical type. In Florida grow evergreen trees entwined with climbers. In the dry subtropical regions on the Pacific coast north of California the vegetation is much poorer. On the watered lands, however, oranges, lemons, apples and grapes are grown.

In the West Indies and in Central America there are tropical forests and savannahs. Man has greatly changed the face of nature in the tropical regions of North America. There are many plantations on which southern fruits, bananas and sugar-cane are grown. The native population is ruthlessly exploited by the United States capitalists who own the plantations.

Questions and Assignments.

1.Trace on the outline map the boundaries of the mixed and deciduous forest regions, the prairies and the desert and subtropical regions of North America.

2.Study the map and examine the natural zones extending along parallel 40° N. Account for the succession of these zones after comparing the zonal and climate maps.

3.Name the animals that inhabit North America today (or recently did) and are not to be found in Europe.

B. SOUTH AMERICA.