SQUIfcKELS 59 



a conditioD, in fact, resembling somewhat that of a 

 hibernating animal. The " diurnal hibernation " of the 

 bat is not to be forgotten. I noticed that my Chip- 

 munk invariably, after feeding, tucked his head down 

 and assumed a more or less ball-like form, highly 

 suggestive of a tendency to hibernation. 



There are many questions that arise in connection 

 with this subject, one of which bears directly on the 

 subject of Comparative Psychology : How and to what 

 extent is the intelligence of animals influenced by 

 hibernation ? It may be considered pretty clear that 

 both the Ground Squirrel and the Flying Squirrel 

 hibernate, and these are certainly among the lowest 

 perhaps are actually the lowest in intelligence of the 

 whole tribe. We know that struggle among higher 

 animals develops mental adaptation and other forms 

 of intelligence, and it is rational to suppose that those 

 species of squirrels that do not hibernate throughout 

 the winter, but endeavour to prevail over their sur- 

 roundings, as well as to adapt themselves to them 

 should be more intelligent than those spending a large 

 portion of each year in inactivity. 



My Chipmunk, during its captivity, under certain 

 circumstances, kept to his original habits, e.g. when a 

 single nut was given him he would eat it immediately, 

 but if several were presented at once he would hide 

 them, one by one, in a corner of his cage, or, if sufficiently 

 small, pack them away in his cheek-pouches. He did 

 the same with cereal grains. When cotton-wool or 

 web-like material was placed in the cage he manipu- 

 lated it a good deal, but finally made a bed of it, in 

 which he buried himself out of sight. 



Within the last ten years attention has been called 

 to " singing " in certain rodents, especially mice ; but 

 from numerous references in the literature it appears 

 that " singing," or something analogous to it, has been 



