PLATE IV. 

 [Twice natural size.] 



. 1. Reithrodontomys humulis humulis. Raleigh, N. C. (No. 189304, U. S. Nat. 

 Mus., Merriam Coll.) 



2. Reithrodontomys humulis Tnerriami. Austin Bayou, Tex. (No. 44849, U. S. 



Nat. Mus., Biological Survey Coll.) 



3. Reithrodontomys albescens griseus. Type, San Antonio, Tex. (No. 87852, 



U. S. Nat. Mus., Biological Survey Coll.) 



4. Reithrodontomys albescens albescens. Type, Kennedy, Nebr. (No. 116358, 



U. S. Nat. Mus., Biological Survey ColL) 



5. Reithrodontomys montanus. Medano Ranch, Costilla County, Colo. (No. 



150714, U. S. Nat. Mus., Biological Survey Coll.) 



6. Reithrodontomys megalotis megalotis. Dry Creek, Socorro County, N. Mex. 



(No. 158319, U. S. Nat. Mus., Biological Survey Coll.) 



7. Reithrodontomys megalotis dychei. Onaga, Kans. (No. 147132, TJ. S. Nat. 



Mus., Biological Survey Coll.) 



8. Reithrodontomys megalotis saturatus. Las Vigas, Vera Cruz. (No. 54434, 



U. S. Nat. Mus., Biological Survey Coll.) 



9. Reithrodontomys raviventris raviventris. Berkeley, Cal. (No. 93208, U. S. 



Nat. Mus., Biological Survey Coll.) 



10. Reithrodontomys raviventris haliccetes. Type, Petaluma, Cal. (No. 7146, 



Mus. Vert. ZooL, Univ. California.) 



11. Reithrodontomys megalotis zacatecx. Valparaiso Mountains, Zacatecas. (No. 



91912, U. S. Nat. Mus., Biological Survey Coll.) 



12. Reithrodontomys megalotis alticolus. Type, Cerro San Felipe, Oaxaca. (No. 



68392, U. S. Nat. Mus., Biological Survey Coll.) 



