PLATE VII. 



[Teeth about 10 times natural size; skulls twice natural size.] 



Figs. 1, 7. Reiihrodontomys (Reithrodontomys) megalotis megalotis. 



Fig. 1. Side view of upper molars. (No. 167353, U. S. Nat. Mus., 



Biological Survey Coll.) 

 Fig. 7. Worn crowns of upper molars. (No. 58090, U. S. Nat. Mus., 

 Biological Survey Coll.) 

 2. Reithrodontomys (Aporodon) tenuirostris aureus. Side view of upper 

 molars. (No. 77008, U. S. Nat. Mus., Biological Survey Coll.) 

 3, 5. Reithrodontomys (Aporodon) levipes. 



Fig. 3. Worn crowns of lower molars. (No. 88057, U. S. Nat. Mus., 



Biological Siuvey Coll.) 

 Fig. 5. Worn crowns of upper molars. (No. 88057, IT. S. Nat. Mus., 

 Biological Survey Coll.) 

 4, 9, 10, 11. Reithrodontomys {Aporodon) mexicanus imexicanus. 



Fig. 4. Worn crowns of upper molars. (No. 68684, U. S. Nat. Mus., 



Biological Survey Coll.) 

 Figs. 9, 10, 11. Skull of type. (No. fj^, Geneva Museum.) 

 6. Reithrodontomys {Aporodon) chrysopsis chrysopsis. Worn crowns of upper 



molars. (No. 125883, U. S. Nat. Mus., Biological Sm*vey Coll.) 

 8. Reithrodontomys (Reithrodontomys) humMlis meiriami. Worn crowns of 

 upper molars, (No. 178261, U. S. Nat. Mus., Biological Survey Coll.) 



