Geographically the cultivated lands to the west and south-west of the middle Jaxartes are divided by the Hissar mountains into two well-defined areas. The northern area includes the rich valley of the Zarafshān and the lesser streams which descend the northern slope of the watershed, the southern comprises the broad basin formed by the Oxus and its tributaries between the mountains of the Pamīr and the steppelands. The former, which as a whole is called Sogdiana in distinction from the smaller principality of _S_ughd, was at this period divided between a number of small states, each independent of the others but forming together a loose confederacy in a manner strikingly reminiscent of the Hellenic city-states. The strongest bond of union was formed by their mutual interest in the Chinese silk trade, the chief stations of which were at Samarqand, Paykand, and Kish. The premier city was Samarqand, the pre-eminence of which and high culture of whose population is vouched for by Yuan Chwang. Special emphasis is laid on their enterprise and success in trade, and a number of early embassies, doubtless commercial missions, are recorded from Samarqand and Bukhārā to the Chinese court. The merchant families of Paykand, according to Tomaschek’s rendering of Narshakhī[8], were Kushans, but Iranian elements, reinforced by emigrants from the Sāsānid dominions, formed the majority in the cities. The agricultural population was almost if not entirely Iranian. A second link between the majority of the cities was formed by the ruling house of the Shao-wu, if, as the Chinese records assert, these all belonged to one royal family. The head of the clan governed Samarqand and was allied by marriage to the Turkish Khan; cadet branches ruled in Ushrūsana, Kish, Bukhārā, and the lesser principalities in the basin of the Zarafshān. In the later lists the rulers of Shāsh and Farghāna as well as the Khwārizm Shāh are shown as belonging to the clan also, though with less probability[9]. Whether the family were of K’ang origin, or, as the Chinese records state, belonged to the Yueh-Chi, they appear in the Arabic histories with Persian territorial titles (Khudāh, Shāh, and the general term dihqān). Some of the princes also possessed Turkish titles, probably conferred on them as vassals of the Khan. The ruler of Samarqand, as king of _S_ughd, is called the Ikhshīdh or Ikhshēdh, which is easily recognised as the Persian _khshayathiya_. This title was borne also, as is well known, by the king of Farghāna. It is certain at least from both Chinese and Arabic accounts that these rulers were not Turks. The Turkish names by which they are sometimes called were given out of deference or compliment to their Turkish suzerains, just as Arabic names begin to appear amongst them immediately after the Arab conquests. Particularly misleading is the name _T_arkhūn which appears more than once in the list of princes of Samarqand and has been