The sterility is most marked on the western flank, which faces the hot rays of the afternoon sun; the eastern slope is occasionally robed with a scanty covering of dwarf oak or stunted brushwood.

In the fat soil of the plains the rivers commonly run deep and concealed from view, unless in the spring and the early summer, when through the rains and the melting of the snows in the mountains they are greatly swollen, and run bank full, or even overflow the level country.
The most important of these rivers are the following:--the Kurnib or Eastern Khabour, which joins the Tigris in lat.

37 deg.

12'; the Greater Zab (Zab Ala), which washes the ruins of Nimrud, and enters the main stream almost exactly in lat.

30 deg.; the Lesser Zab (Zab Asfal), which effects its junction about lat.