CLASS MAMMALIA. 61 



Mus musculus, Linn. COMMON MOUSE. 



Who does not know this foul-smelling, but nevertheless 

 pretty, little beast? It abounds everywhere, and has followed 

 man to all parts of the world. Houses, buildings, and corn- 

 ricks are its favourite haunts, and it does not occur in this 

 country except in their vicinity. Its original home certainly 

 was not in Britain. 



Albinos occasionally occur wild. In February, 1897, 

 nearly a score of white specimens, having pink eyes, were 

 caught in threshing a stack of wheat on Stebbing Ford Farm, 

 Felstead (Essex County Chronicle, February 26th, 1897). 



Mus rattus, Linn. BLACK RAT. 



This, our oldest Rat, was abundant before the advent of 

 the Brown Rat, called by Waterton and others the " Han- 

 overian Rat." It is now almost extinct, although still occurring 

 about the docks and other places in the East-end of London. 

 The specimens thus met with may not be natives. Probably 

 the race is kept up by escapes from the vessels lying in the 

 river in the neighbourhood. 



Mr. H. Barclay records (Zoo/., 1848, p. 616) the trapping 

 of an immature specimen in a dry bank at Leyton. Two 

 others were also taken near the same place. 



The Black Rat is easily known from the Hanoverian Rat 

 by the size of its ears, the slenderness and length of its 

 tail, and by the mouth appearing to be so far under 

 the nose. 



In habits and feeding, there is much in common between 

 the two species. Mus rattus, however, confines itself to the 

 upper parts and roofs of buildings : Mus decumanus, to the 

 basements and drains. 



