Quercus Ilex, the evergreen oak of southern Europe, is found in forests as far east as the Sutlej, accompanied with other European forms. In the higher parts of Afghanistan and Persia Boraginaceae and thistles abound; gigantic Umbelliferae, such as Ferula, Galbanum, Dorema, Bubon, Peucedanum, Prangos, and others, also characterize the same districts, and some of them extend into Tibet.
Sequoia and the tulip-tree still remain; figs are abundant; laurels are represented by Sassafras and camphor; herbaceous plants (Ranunculaceae, Cruciferae, Umbelliferae) are present, though, as might be expected, only fragmentarily preserved.
The former is poor in Cruciferae, Caryophyllaceae, Umbelliferae, Primulaceae and Labiatae; but for the occurrence of Calluna in Newfoundland it would have no heaths.
It is even richer in more herbaceous plants tolerant of a hot summer; giant Umbelliferae (such as Ferula) are especially characteristic and yield gum-resins which have long been reckoned valuable.
This is illustrated in the "harbinger of spring," a name given to a small plant belonging to the Umbelliferae, which has a tuberous root, and small white flowers; it is found in the central states of North America, and blossoms in March.