32 Field Museum of Natural History — Zoology, Vol. XL 



Subgenus OCHROTOMYS. 

 Peromyscus ?iut.talli aureolus (AuD. and Bacfl). Southern Golden Mouse. 

 Genus REITHRODONTOMYS. 



[Reithrodontomys dychei Allen. Dj'che's Harvest Mouse] 



Genus ORYZOMYS. 

 Oryzomys palustris (Harlan). Rice Field Mouse. 



Subfamily NEOTOMIN.E. 



Genus NEOTOMA. 

 Subgenus NEOTOMA. 

 Neotoma floridana illinoensis Howell. Illinois Wood Rat. 



Subfamily MICROTIN.f:. 

 Genus EVOTOMYS. 



Evotomys gapperi (Vigors). Red-backed Mouse or Vole. 



Genus MICROTUS. 



Subgenus MICROTUS. 

 Microtus pennsylvanicus (Ord). Meadow Mouse or Vole. 



Subgenus PEDOMYS. 

 Microtus ochrogaster (Wagner). Prairie Meadow Mouse or Vole. 

 [Microtus minor Merriam. Little Meadow Mouse or V^ole.] 



Subgenus PITYMYS. 

 Microtus pinetorum scalopsoides (Aud. and Bach.). Mole Mouse or Mole-like Vole. 



Genus FIBER. 

 Fiber zibethicus (Linn.). Muskrat. 



Genus SYNAPTOMYS. 

 Subgenus SYNAPTOMYS. 

 Synaptomys cooperi Baird. Cooper's Lemming Mouse.]* 

 Synaptomys cooperi gossii (Merriam). Goss's Lemming Mouse. 

 Synaptomys cooperi faluus (Bangs). Bangs's Lemming Mouse. 



Family GEOMYID.E. Pocket Gophers. 

 Genus GEOMYS. 

 Geomys bursarius (Shaw). Pocket Gopher. 



Family ZAPODID^. Jumping Mice. 

 Subfamily ZAPODIN^E. 

 Genus ZAPUS. 

 Zapus hudsoniiis (Zimm.). Hudson Bay Jumping Mouse. 



Genus NAP^OZAPUS. 

 [NapcEozapus insignis (Miller). Woodland Jumping Mouse.] 



*I have seen no typical specimens of S. cooperi from Illinois, but specimens from the east 

 central part of the state are intermediate between cooperi and gossii. 



