MACROGEOMYS. 327 
frontal flat, depressed medianly, broad; postorbital processes large; 
palato-pterygoids short, broad, truncate posteriorly; braincase high 
above root of zygoma; lambdoid crest straight; occipital plane flat, 
sloping forward; upper premolar with four enamel plates; first upper 
and second lower molars with two enamel plates each; last upper 
1 
molar with lengthened heel and deep outer sulcus; upper incisor with 
only one narrow deep sulcus on inner third of face. 
Fic. 62. MACROGEOMYS CHERRII. 
No. g07o Am. Mus. Nat. Hist. Coll. Nat. size 
