Note 495 — BOOK VI. AN ACCOUNT OF COUNTRIES, NATIONS, SEAS, TOWNS, HAVENS, MOUNTAINS, RIVERS, DISTANCES, AND PEOPLES WHO NOW EXIST, OR FORMERLY EXISTED.
John Bostock translation
The Parthi originally inhabited the country south-east of the Caspian, now Khorassan. Under Arsaces and his descendants, Persis and the other provinces of ancient Persia became absorbed in the great Parthian empire. Parthia, with the Chorasmii, Sogdii, and Arii, formed the sixteenth satrapy under the Persian empire. See c. 16 of this Book.