Page:Mongolia, the Tangut country, and the solitudes of northern Tibet vol 2 (1876).djvu/107

Rh Koko-nor, in the snowy range south of Si-ning, and in the Yegrai-ula, near the sources of the Yellow River. We could not ascertain positively if it grows in the neighbouring province of Sze-chuan, but it is not found in Northern Tibet. Thus from all the information we could gather, it is limited to the alpine country of Lake Koko-nor and the sources of the Yellow River.

Another kind (Rheum spiciforme) is also found in the Kan-su mountains, where it only grows in the alpine region. This plant has a thin branched root about four feet long, but is unfit for medicinal purposes. It grows in the Himalayas and Thian Shan, and we often saw its withered leaves in winter in Northern Tibet.

We have already said that the forests grow 10,000 feet above sea-level; higher than this they are replaced by alpine bushes and by meadows; the rhododendra, of which we found four kinds — all pronounced to be new by the botanist Maximovitch