THROWING BACK S3 



albino is as great as that between the colour of 

 the two. 



Though I did not make pets of my albinos, they 

 were perfectly tame, and would very seldom attempt 

 to escape from the cage when it was opened. But 

 the greatest caution had to be exercised when a 

 cage containing first crosses was opened, for if care is 

 not taken the mouse will spring from the nest directly 

 the lid is lifted, and be lost. I lost one or two mice 

 in this way before I learnt this characteristic of the 

 first crosses. But even if the mouse does not escape, 

 the wildness of its disposition is manifested in the 

 frenzied way in which it darts about the cage when 

 it is subjected to treatment (such as mating up, or 

 the separation of the males from the females in a 

 family when they become adult) under which the 

 albino behaves with perfect tameness. The excessive 

 vigour of the first cross is manifested also in the 

 glossy condition of its coat, which I have always 

 noticed to be much sleeker than that of any of the 

 other mice — its parents or its offspring — in my 

 experiments. 



The phenomenon of the inheritance of colour in 

 these mice has now been described ; and the appli- 

 cation of the knowledge of this and the other results 

 which we have discussed, has been briefly referred 

 to. The luxuriant " condition " of the hybrid has 

 been illustrated, and this reference to a physiological 

 character leads naturally on to the consideration of 

 another character in respect of which the two parent 



