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IOWA ACADEMY OP SCIENCE 
Sub-family MURINAE. 
Genus MUS Linnaeus. 
29. Mus decumanus Pallas. Brown Rat; Wharf Rat; Norway Rat. “A cos- 
mopolitan species; introduced into America about 1775” Jordan. 
Common all over the state. 
30. Bins musculus Linnaeus. Common House Mouse. Cosmopolitan; probably 
introduced about the same time as the preceding species. 
Common all over the state. 
Family CASTORIDAE. (The Beavers.) 
Genus CASTOR Linnaeus. 
31. Castor canadensis Kuhl. American Beaver. 
Formerly occurred all over the state; became extinct sometime in the 
nineties. 
Family SCIURIDAE. (The Squirrels.) 
Genus ARCTOMYS Schreber. 
32. Arctomys monax Linnaeus. Woodchuck; Ground Hog; Marmot. 
Sparingly over the state. 
Genus SPERMOPHILUS Cuvier. 
33. Spermophilus franklini Sabine. Gray Gopher; Scrub Gopher; Prairie 
Squirrel. 
Common all over the state. ‘ 
34. Spermophilus tridecemlineatiis Mitchell. Striped Gopher; Striped Ground 
Squirrel; Thirteen-lined Squirrel. 
Common all over the state. 
Genus CYNOMYS Rafinesque. 
35. Cynomys liidovicianus Ord. Prairie Dog. 
“Knew of one specimen in Cass County several years ago.” Pellett. 
Genus TAMIAS Illiger. 
36. Tamias striatus Linnaeus. Chipmunk; Ground Squirrel. 
Sparingly all over the state. 
37. Tamias striatus griseus Meaens. 
Occurs ill Missouri; probably in Iowa. 
Genus SCIURUS Linnaeus. 
38. Sciurus hudsonicus loquax Bangs. Southern Red Squirrel. 
“Have taken them in low^a.” Pellett. 
39. Sciurus carolinensis Gmelin. Gray Squirrel; Black Squirrel; Cat Squirrel. 
Common over eastern and southeastern Iowa. 
40. Sciurus carolinensis liypopliaeus Merriam. Large Gray Squirrel. 
Occurs in southern Minnesota; very probably in Iowa. 
41. Sciurus ludovicianus Custus. Western Pox Squirrel. 
Common in Iowa. 
