THE WATER RAT 



497 



renders the microtines generally such easy victims of pit- 

 traps. 



The British Water Rat has not been frequently tamed, but 

 M. Lataste kept specimens of two continental forms,^ some of 

 the peculiarities of which have been mentioned above. Mr 

 English ^ has also caged them ; though thriving well in 

 captivity, they are rather troublesome, requiring a large tank of 

 water,^ which they immediately soil with their droppings and 

 making their cage and nest constantly wet after their aquatic 

 excursions. Cocks has also frequently caged numbers of them, 

 but for the above reason he has never kept them systematically, 

 but has always used them as required, as very suitable food for 

 Wild Cats. Some of M. Lataste's captives showed a tendency 

 to arrange their bed near the water in such a position that they 

 could drop into that element unseen if disturbed ; although 

 very assiduous in working at their nest they evidently felt most 

 secure in the water. 



The intelligence of the Water Rat is considerable, and it is 

 capable of recognising particular persons ; but in the opinion 

 of M. Lataste it is in this respect inferior to the Brown Rat. 



The maximum age attained in the London Zoological 

 Gardens is i6 months,* but the natural life of the animal is 

 probably much longer. 



Sub-family Murince. 



Characters: — The members of this sub-family, the typical 

 mice and rats, are of varied external appearance and habits. 

 They differ from the Microtince chiefly in being more perfectly 

 adapted for gnawing ; in retaining a preference for, and 

 consequently a dentition suitable to the treatment of, a soft 

 and succulent diet ; and in leading more active and Jess 

 earthbound lives. Their eyes and external ears are always 

 well developed. 



* A. sapidus and A. scherman. ^ In Millais, ii., 293, etc. 



^ If not allowed to swim their eyes become closed by secretion of an oily matter 

 drying like white wax (English). * P. Chalmers Mitchell. 



