<P> The xerophytic vegetation consists of aloes, mesembryanthemums, crassulas, euphorbias, stapelias, and desert ephemerals, spaced 50 cm or more apart, and becoming very sparse going northwards into Bushmanland and, from there, into the Kalahari Desert . The driest region of the Karoo, however, is its southwestern corner, between the Great Escarpment and the Cederberg - Skurweberg mountain ranges, called the Tankwa Karoo, which receives only 75 mm of rain annually . The eastern and north - eastern Karoo are often covered by large patches of grassland . The typical Karoo vegetation used to support large game, sometimes in vast herds . </P> <P> Today sheep thrive on the xerophytes, though each sheep requires about 4 hectares of grazing to sustain itself . </P> <P> The Karoo is sharply divided into the Great Karoo and the Little Karoo by the Swartberg Mountain Range, which runs east - west, parallel to the southern coastline, but is separated from the sea by another east - west range called the Outeniqua--Langeberg Mountains . The Great Karoo lies to the north of the Swartberg range; the Little Karoo is to the south of it . </P> <P> The only sharp and definite boundary of the Great Karoo is formed by the most inland ranges of Cape Fold Mountains to the south and south - west . The extent of the Karoo to the north is vague, fading gradually and almost imperceptibly into the increasingly arid Bushmanland towards the north - west . To the north and north - east it fades into the savannah and grasslands of Griqualand West and the Highveld . The boundary to the east grades into the grasslands of the Eastern Midlands . The Great Karoo is itself divided by the Great Escarpment into the "Upper Karoo" (generally above 1200--1500 m) and the "Lower Karoo" on the plains below at 700--800 m . A great many local names, each denoting different subregions of the Great Karoo, exist, some more widely, or more generally, known than others . In the Lower Karoo, going from west to east, they are the "Tankwa Karoo", the "Moordenaarskaroo", the "Koup", the "Vlakte" and the "Camdeboo Plains". The "Hantam", the "Kareeberge", the "Roggeveld" and "Nuweveld" are the better known subregions of the Upper Karoo; though most of it is simply known as the "Upper Karoo", especially in the north . </P>

Name the folded mountains of the western cape that enclose the little karoo