when i found in la plata the tooth of a horse embedded with the remains of mastodon, megatherium, toxodon, and other extinct monsters, which all co-existed with still living shells at a very late geological period, i was filled with astonishment; for, seeing that the horse, since its introduction by the spaniards into south america, has run wild over the whole country and has increased in numbers at an unparalleled rate, i asked myself what could so recently have exterminated the former horse under conditions of life apparently so favourable.

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When I found in La Plata the tooth of a horse embedded with the remains of Mastodon, Megatherium, Toxodon, and other extinct monsters, which all co-existed with still living shells at a very late geological period, I was filled with astonishment; for, seeing that the horse, since its introduction by the Spaniards into South America, has run wild over the whole country and has increased in numbers at an unparalleled rate, I asked myself what could so recently have exterminated the former horse under conditions of life apparently so favourable.