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 

 molar with lengthened heel and deep outer sulcus ; upper incisor with 

 only one narrow deep sulcus on inner third of face. 



FIG. 62. MACROGEOMYS CHERRII. 



No. 9070 Am. Mus. Nat. Hist. Coll. Nat. size. 



