• WordNet 3.6
    • n mesohippus North American three-toed Oligocene animal; probably not directly ancestral to modern horses
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Webster's Revised Unabridged Dictionary
    • n Mesohippus (Paleon) An extinct mammal of the Horse family, but not larger than a sheep, and having three toes on each foot.
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Century Dictionary and Cyclopedia
    • n mesohippus A genus of very small three-toed horses, of the family Equidæ founded by Marsh in 1875 upon remains from the early Miocene of North America. The animal was only about as large as a sheep, with three functional digrits on each foot, and an additional splint-bone on each of the fore feet.
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Webster's Revised Unabridged Dictionary
NL., fr. Gr. me`sos middle + a horse


In literature:

The genus Mesohippus, of the middle Oligocene, may be selected as a kind of half-way stage in the long progression.
"Darwin and Modern Science" by A.C. Seward and Others
All the known species of this genus are larger than those of Mesohippus, and none of them pass above the Miocene formation.
"Darwinism (1889)" by Alfred Russel Wallace
Three-toed horse, Mesohippus, about the size of a sheep.
"The Outline of Science, Vol. 1 (of 4)" by J. Arthur Thomson

In science:

Eohippus-Mesohippus-Equus sequence many of us learned as children.
Astrophysics in 2005