These run in wet seasons, but in every instance for a short distance only, and sooner or later they are lost in sand-hills, where their waters disappear and a line of stunted gum-trees (Eucalyptus rostrata) is all that is present to indicate that there may be even a soakage to mark the abandoned course.
Putting aside the exotic vegetation of the north and east coast-line, the Australian bush gains its peculiar character from the prevalence of the so-called gum-trees (Eucalyptus) and the acacias, of which last there are 300 species, but the eucalypts above all are everywhere.
The forest vegetation, largely confined to the "Isle of Isles" and the southern uplands, includes the Adansonia (baobab), which in the Fazogli district attains gigantic proportions, the tamarind, of which bread is made, the deleb palm, several valuable gum trees (whence the term Sennari often applied in Egypt to gumarabic), some dyewoods, ebony, ironwood and many varieties of acacia.
European fruit trees and vines flourish in certain localities, while in the drier regions the Australian wattle, gum trees and pepper trees have been introduced with success.
Among the many varieties of trees and plants found are the date palm, mimosa, wild olive, giant sycamores, junipers and laurels, the myrrh and other gum trees (gnarled and stunted, these flourish most on the eastern foothills), a magnificent pine (the Natal yellow pine, which resists the attacks of the white ant), the fig, orange, lime, pomegranate, peach, apricot, banana and other fruit trees; the grape vine (rare), blackberry and raspberry; the cotton and indigo plants, and occasionally the sugar cane.