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As a matter of fact, wild animals, or even domesticated animals in nearly a wild state, do _not_ eat the poisonous plants of the country in which they and their forefathers have been brought up--that is provided that they are either adult or are accompanied by full-grown animals. Almost every case of cattle-poisoning in Great Britain occurs when young calves, foals, or lambs are turned loose in the fields without any mature older head amongst them. Sometimes valuable stable-bred animals are lost, especially by eating yew-leaves, but there are exceedingly few instances of full-grown cattle being caught in such foolishness. When cattle, horses, or sheep are turned loose in a new country, plenty of cases do occur, and it is possible that they might make mistakes with unknown foreign plants which had escaped into their pastures here.