What is "elephas primigenius"

Mammoth \Mam"moth\ (m[a^]m"m[o^]th), n. [Russ. m[^a]mont, m['a]mant, fr. Tartar mamma the earth. Certain Tartar races, the Tungooses and Yakoots, believed that the mammoth worked its way in the earth like a mole.] (Zo["o]l.) An extinct, hairy, maned elephant ( Mammuthus primigenius formerly Elephas primigenius), of enormous size, remains of which are found in the northern parts of both continents. The last of the race, in Europe, were coeval with prehistoric man.

Note: Several specimens have been found in Siberia preserved entire, with the flesh and hair remaining. They were imbedded in the ice cliffs at a remote period, and became exposed by the melting of the ice.