GEOIvOGY OF LA SALLK COUNTY. 



75 



long-, very destructive to poultry, is not uncommon. 



Rats — The black rat — Mus rattus, was common 

 in early days, now extinct; was brouo-ht to America in 

 1544; is generally exterminated by Mus decumanus. 



The Norway Rat — Mus decumanus — appeared 

 soon after the settlement of the country beg^an, and is 

 found ever}^ where. Broug-ht to America in 1775. It is 

 often called wharf rat. 



Jumping Mouse or Long-tailed Mouse — Za- 

 pus hudsonius — is found in the timber; rather scarce. 



The Deer Mouse, Short-tailed Mouse, 

 White-footed Mouse. — Hesperomys leucopus— is 

 very common, and often called meadow mouse or field 

 mouse. It is probable H. Michig-anensis and Arvicola 

 Pennsylvanicus are included in the last. The com- 

 mon mouse or house mouse — Mus musculus — was 

 found here, and was in the early days more trouble- 

 some than at present. 



The Opossum — Didelphys Virg-iniana — is said to 

 have immig-rated to this part of the world after its 

 settlement. It has nearly, if not entirely, disappeared. 



The Mole — Scalops arg-entatus — the prairie 

 mole is very common and a very troublesome visitor in 

 g-ardens. It is larg-er than the common mole and more 

 silvery in color. S. aquaticus — the common mole, is 

 probably an inhabitant of the county. We presume 

 also the star-nosed mole Condylura cristata. 



The Bat — Tl^e little brown bat— Vespertilio sub- 

 ulatus — a small olive brown animal is frequently seen; 

 also probably V. noctivag-anns, larg-er, and hair wHth 

 silvery tips. The red bat — Atatapha noveboracensis— 

 is sometimes met with. It is reddish brown, three 

 and three-fourths inches long-. 



