660 MURID^— MUS 



Mice at the sixth day commenced to be clothed, at the 

 thirteenth day they were completely clothed, and had the 

 external auditory meatus open ; at the fourteenth to the fifteenth 

 day the eyes opened ; on the nineteenth day (but sometimes 

 as early as the sixteenth) they were able to leave the mother, 

 although they would suckle for a few days more if opportunity 

 permitted ; at this age their parents do not molest them, but 

 soon after they will massacre the young. The male will 

 copulate when i|- months old, and a female ii6 days old 

 bore young after copulation with a male of her own age. 

 Lataste observed them to be very voiceful, crying at birth. 

 Saint- Loup ^ finds the rate of growth to be most rapid 

 immediately after birth ; it then decreases continually during 

 eighteen days ; from the nineteenth to the twenty-second day 

 it rises again, but without attaining a quarter of the initial 

 rate ; afterwards it fluctuates. 



Despite their disagreeable odour, which impregnates their 

 cages and everything they touch, many find tame House Mice 

 attractive pets ; there is a National Mouse Club, and " shows " 

 are held at which prizes are awarded to the best representatives 

 of the very numerous recognised classes or breeds. These 

 mice have long been tamed, and certain of the coloured races 

 are of respectable antiquity; thus Merrett [Pinax, 167, 1667) 

 was acquainted with white, ashy and dark varieties, and it is 

 worth noting that he does not speak of coloured rats. Brehm 

 [Tkierleben, ii., 134) states that tame mice are fond of spirits, 

 but Lataste found that pure rum had no attraction for those 

 kept by him. The latter writer describes his captives as 

 being essentially, though not absolutely, nocturnal ; with well- 

 developed senses, and intelligent, though not so well endowed 

 in these respects as the Brown Rat ; they are excellent climbers, 

 with feebly, but really, prehensile tails, which are especially 

 useful to them in balancing exercises, in which they excel; 

 they have a sense of property, and are peculiarly gentle, 

 perhaps from long domestication, and readily handled ; they 

 are friendly to each other, unless treated foolishly or badly 

 fed ; a single cage, however, will only hold the parents and 

 young, and the young must be removed when they become 



^ R. Saint- Loup, Bull. Zool. de France, 1893, 242. 



