Nesodon (formerly Adinotherium) ovinum.
<bdi><a href="https://en.wikipedia.org/wiki/en:Robert_Bruce_Horsfall" class="extiw" title="w:en:Robert Bruce Horsfall"><span title="American painter">Robert Bruce Horsfall</span></a>
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<a rel="nofollow" class="external text" href="https://archive.org/stream/historyoflandmam00scot#page/n9/mode/2up">A History of Land Mammals in the Western Hemisphere</a>, page 474