Strabo, Geography
H.C. Hamilton, Esq., W. Falconer, M.A., Ed.

It is a custom peculiar to all the Scythian and Sarmatian tribes, to castrate their horses, in order to make them more tractable, for although they are small, yet they are spirited, and difficult to manage. Stags and wild boars are hunted in the marshes, and wild asses and roes¹ in the plains. It is a peculiarity of this country, that no eagles are to be found in it. Among the quadrupeds there is an animal called Colus, in size between a deer and a ram; it is white, and swifter in speed than either of those animals. It draws up water into the head through the nostrils; from this store it can supply itself for several days, and live without inconvenience in places destitute of water.

Such is the nature of the whole of the country beyond the Danube, lying between the Rhine and the Don, and extending as far as the Pontic Sea and the Palus Mæotis.