428 



REPORT OF STATE GEOLOGIST. 



bers.' This is due in part to their shy disposition, small economic 

 importance, and the destruction of their natural enemies. 



The white-footed mice, two voles, four shrews and mole, which 

 are the remaining species of the group, are all small and inconspic- 

 uous. Evidence as to their former abundance is not at hand, but 

 it is very probable that they have increased rather than diminished. 

 It should be noted, however, that very little is known concerning 

 the habits and habitat of the long-tailed shrews (Sor&x) in this 

 State, and on account of their rarity they should perhaps be in- 

 cluded among those that are holding their own. 



In the last group of 16 species I have included the beaver, 

 muskrat and water hare, the introduced mice and rats and the bats. 

 The first of these species disappeared early, being killed for the 

 value of its fur and castoreum. Its habit of congregating in large 

 communities about the water aided in its extermination. Repeated 

 breakings of the beaver dams often caused the animals to leave a 

 locality where they were disturbed, even though some of the colony 

 escaped the trappers. 



The muskrat has habits similar to those of the beaver, but it 

 is not trapped so persistently, because its fur is less valuable. It 

 reproduces much more rapidly and adapts itself more readily to its 

 surroundings. Therefore, muskrats have been able to survive in 

 every part of the State, and their numl)ers have been reduced more 

 on account of draining the swamps than because of killing the 

 animals. 



Four species of the mouse family have been introduced by man. 

 The black rat came with the earliest settlers and was driven out 

 in the first half of the last century by the larger Norway rat. More 

 recently individuals have been reintroduced but have not become 

 re('stablished. The Norway rat and house mou«^e have been house- 

 hold pests for centuries and are able to hold their own in the im- 

 mediate surroundings of man. A red rat has been occasionally in- 

 troduced with fruit brcmght from the tropics, l)ut has never be- 

 come established. 



The nine species of bats constitute a peculiar part of the fauna 

 of the State. They make their homes in hoUow trees, garrets, de- 

 s(5rted buildings and caves. The guides at Wyandotte Cave state 

 tliHt they are less numerous there than formerly, but I have no 

 oth(ir evidence as to the pi'esent and past numbers of these animals, 

 and there is little reason to believe that they have either increased 

 ()!• decrejised in number. 



In sinnrnari/ing the above facts (see table) it, must be admitted 



