HEREDITY OF WILDNESS AND SAVAGENESS IN MICE 9 



Biting in this case is not, however, always a sign of savageness. 

 Quoting from the writer's notes; "Biting when just caught is 

 not always a sign of savageness for tame individuals will bite 

 if hurt." This is corroborated by Miss Abbie E. C. Lathrop, 

 Granby, Mass., who has had many years' experience in breed- 

 ing and handling mice. The following statements are taken 

 from one of her letters. "Every one who comes here and tries 

 to handle mice gets bitten even by tame mice, because of grasp- 

 ing the tail too tightly. Some mice are cross even when not 

 hurt, but gentle mice resent pain and bite." 



The chief indications of savageness are biting and squeaking. 

 A mouse possessing the greatest degree of savageness may 

 indicate this by biting in either of two ways depending largely, 

 it seems, upon the degree of wildness which accompanies it. 

 Very often a very savage mouse while being pulled from the 

 nest and before the hand has touched its body will swing about 

 and sink its teeth into the glove. This act is the nearest ap- 

 proach to the offensive savageness of the rat. If there is a 

 great degree of wildness present which will cause it to make 

 violent attempts to free itself, everytime that its feet touch a 

 part of the glove in its frightened jumping about the teeth 

 are vigorously used. Often in the instant before the next 

 jump two or three bites will be made in the glove, the mouse 

 trying, as it were, to find some vulnerable spot. If the glove 

 has even a small hole in it in an accessible spot the mouse of 

 this type is very apt to find it and use its teeth with considerable 

 effect. 



On the other hand, if there is a much less degree of wildness 

 present the mouse will often seize the glove with its teeth 

 and tenaciously hold on until compelled to let go by the experi- 

 menter whereupon it will immediately fasten its teeth in another 

 part of the glove. The mouse with no savageness will make 

 no attempt to bite even when teased unless the tail is held too 

 tightly or it is otherwise hurt. However, many of the non- 

 savage mice made no attempt to bite even when being numbered. 



Between these two extremes of savageness there are many 

 types of behavior which were considered as representing 

 different grades of savageness as, for instance, the mouse with a 

 low degree of savageness will, perhaps, use its teeth but once 

 or twice during the test and then only in an indifferent way, 



