The animals too which Xenophon found in the country are either such as now inhabit it, or where not such, they are the denizens of hotter rather than colder climates and countries.
The fertility of Assyria is a favorite theme with the ancient writers.
Owing to the indefiniteness of their geographical terminology, it is however uncertain, in many cases, whether the praise which they bestow upon Assyria is really intended for the country here called by that name, or whether it does not rather apply to the alluvial tract, already described, which is more properly termed Chaldaea or Babylonia.
Naturally Babylonia is very much more fertile than the greater part of Assyria, which being elevated above the courses of the rivers, and possessing a saline and gypsiferous soil, tends, in the absence of a sufficient water supply, to become a bare and arid desert.

Trees are scanty in both regions except along the river courses; but in Assyria, even grass fails after the first burst of spring; and the plains, which for a few weeks have been carpeted with the tenderest verdure and thickly strewn with the brightest and loveliest flowers, become, as the summer advances, yellow, parched, and almost herbless.

Few things are more remarkable than the striking difference between the appearance of the same tract in Assyria at different seasons of the year.

What at one time is a garden, glowing with brilliant hues and heavy with luxuriant pasture, on which the most numerous flocks can scarcely make any sensible impression, at another is an absolute waste, frightful and oppressive from its sterilityr.
If we seek the cause of this curious contrast, we shall find it in the productive qualities of the soil, wherever there is sufficient moisture to allow of their displaying themselves, combined with the fact, already noticed, that the actual supply of water is deficient.

Speaking generally, we may say with truth, as was said by Herodotus more than two thousand years ago--that "but little rain falls in Assyria," and, if water is to be supplied in adequate quantity to the thirsty soil, it must be derived from the rivers.