72 MAMMALS. 



The food of the black rat is varied, though its preference 

 is unquestionably for vegetable matter. 



The rats need little descrijDtion, their typical appearance 

 being too familiar. In colour the present species has a good 

 deal of grey in its fur, though its common name 

 Appearance, ggj^^gg ^^ distinguish it from the other species. 

 The short lower jaw of the black rat gives the 

 face a shrew-like expression. The ears are large and naked. 

 The tail, longer than the head and body, is nearly naked 

 and ringed with scales. The feet are plantigrade, the hind- 

 feet with five well-developed toes, the forefeet with four 

 toes and a rudimentary clawed thumb. 



The Brown Rat, easily distinguished by its superior size, 

 is the rat commonly met with in this country, where it has 

 all but ousted its smaller black relative, just 

 as, in the Antipodes, it has driven to extinc- 

 tion the possibly apocryphal Maori rat of New Zealand. 

 It is wrongly called the Hanoverian or Norway rat, and 

 would a23]3ear to have been introduced at the end of the 

 seventeenth century. 



Its food is still more varied than that of the last species, 



as it is not only carnivorous at certain seasons, but is also 



known to relapse on very slight provocation 



into cannibalism. Game, fish, young birds, 



eggs, frogs, snails, truffles, and grain, are among the 



articles on which it commonly feeds ; and it is also known 



to gnaw hard substances from which it could not possibly 



derive any nourishment, in the endeavour, possibly, to keep 



its teeth worn to the proper level. It is a i^owerful 



swimmer, and I remember seeing one night in Sydney 



Harbour a large number of these rats leaving a ship, 



having in all i)robability exhausted the food suj^ply. 



If anything, this species is even more prolific than the 



. last, as many as twelve having often been 



recorded in one litter, though the number of 



