Note 2917 — BOOK IV. AN ACCOUNT OF COUNTRIES, NATIONS, SEAS, TOWNS, HAVENS, MOUNTAINS, RIVERS, DISTANCES, AND PEOPLES WHO NOW EXIST OR FORMERLY EXISTED.
John Bostock translation
According to Parisot, the Guttalus is the same as the Alle, a tributary of the Pregel. Cluver thinks that it is the same as the Oder. Other writers again consider it the same as the Pregel.