The Collaborative International Dictionary of English v.0.48:

Paleotherian \Pa`le*o*the"ri*an\
   (p[=a]`l[-e]*[-o]*th[=e]"r[i^]*an), a. [F.
   pal['e]oth['e]rien.] (Paleon.)
   Of or pertaining to Paleotherium.
   [1913 Webster]