The eastern division of the Atlas, which forms the backbone of Algeria and Tunisia, is adequately known with the exception of the small portion in Morocco forming the province of Er-Rif.
The present writer believes that the date palm was really indigenous to this district of the Jerid, as it is to countries of similar description in southern Morocco, southern Algeria, parts of the Tripolitaine, Egypt, Mesopotamia, southern Persia and north-western India; but that north of the latitude of the Jerid the date did not grow naturally in Mauretania, just as it was foreign to all parts of Europe, in which, as in true North Africa, its presence is due to the hand of man.
The Argan tree (A rgania Sideroxylon), which forms forests in Morocco, is a remarkable survivor of a tropical family (Sapotaceae).
Ballota, a closely allied species abundant in Morocco, bears large edible acorns, which form an article of trade with Spain; an oil, resembling that of the olive, is obtained from them by expression.
The centre of the traffic in Morocco was Sidi Hamed ibn Musa, seven days' journey south of Mogador, where a great yearly fair was held.