Less dreaded, and far less frequent than these depredations, are attacks upon caravans by wolves. These occur scarcely once in ten years, and then only in very severe winters, when long frosts keep the flocks from the pastures. Under such circumstances, the wolves, spurred by extreme hunger, sometimes overcome their natural cowardice, and make a dash at a caravan, breaking suddenly into the column on the march, pulling down horses, and tearing them in pieces, before there is time to drive them away with bullets. But these cases are of extremely rare occurrence. It more often happens that, in summer, a single wolf will sneak down upon the grazing caravan horses, whose instinct, however, soon detects his approach. They form a circle, heads inwards and heels out, and if the wolf does not succeed, at a first spring, in fixing upon one of their throats, his best plan is to decamp, before he gets shot. The attacks of these wolves are always nocturnal. From other beasts of prey the caravans between Erzroum and Tabriz have nothing to fear. The jackals are weak and timid, and content themselves with dead horses; and bears are few in number, and confine their feeding to sheep and goats. Southwards from Tabriz to Teheran, and thence to Ispahan, the danger increases. Kourds are replaced by Turkomans; wolves by panthers and tigers. But even from these, so far as Dr Wagner could gather from repeated conversations with caravan leaders, the peril is trifling, except far south, towards Shiraz, or eastwards in the deserts of Khorassan, where tigers are more numerous and aggressive.