ORDEK RODENTIA. 131 



covered with small parallelograms of epidermis ranged in 

 circles around it, and underneath the extremity of each 

 lamina of epidermis grow some small gray hairs. The hairs 

 which cover the limbs and the head are short. The mus- 

 tachios are black, and the soles of the feet, which are 

 naked, are flesh-coloured, as are also the ears and extremity 

 of the muzzle. 



No personal description of the Common Domestic Mouse, 

 an animal known to every one, seems to be required. The 

 organization of this little species accords in all respects 

 with that of the Common or Black Rat, and the Brown or 

 Surmulot Rat, consequently it agrees with those animals 

 pretty generally in all its habits and modes of life, as far as 

 the disparity of size and strength will permit, except per- 

 haps that the Mouse may be said to have less energy of 

 character, less resolution and determination, than the Rat, 

 even after their relative powers have been duly estimated. 



When the parasitical habits of the Mouse, in regard to 

 man, are considered, and he may be said to be exclusively 

 a resident in our common habitations, we seem naturally 

 led to inquire what the habits of the animal were before 

 the progress of human civilization had furnished him with 

 his present means and modes of living. Analogy would 

 lead us to the conclusion that hollow trees, clefts in rocks, 

 and perhaps the burrows of other quadrupeds, may have 

 furnished the Mouse with a residence before the artificial 

 and permanent habitations of mankind supplied him with a 

 more congenial domicile; but we have few facts in support 

 of such conclusion, and so completely is this little trouble- 

 some inmate now attached to civilized life, that he has 

 migrated with us to all the parts of the earth to which 

 industry and enterprize have carried us. 



Mice, though found in such numbers in a single house, 

 cannot be called social animals ; each lives insulated, for 

 himself alone, except when the universal fiat " increase and 



