ANIMAL BEHAVIOR—ERNEST P. WALKER 285 
uses this method to take her baby under water with her out of danger. 
Seals may do it for the same reason. 
Recently my wife and I witnessed a female black individual of the 
gray squirrel of the eastern United States collecting bark fiber for her 
nest. She went onto a dead limb of a tulip tree about 8 feet from our 
window and began loosening a strip of bark about a foot in length. 
Some was torn loose entirely but left hanging by a small strand, other 
parts were not hanging down but were well loosened from the branch. 
I thought at first she was not satisfied with the quality of the bark, 
and I was about ready to offer her advice on how to collect bark 
without wasting so much of it. Finally she began picking up the 
hanging fibers in her mouth, placing them crosswise and tucking the 
ends in so they would not drag and be in her way. When she came 
to the strands that still kept the pieces of bark attached to the limb 
she cut them off. In a few instances she backed up and pulled them 
loose by tugging. I then realized that she did not need any advice 
on how to gather bark with her equipment. She had loosened all the 
bark she needed but left it attached so it would not fall to the ground, 
then when she had enough loosened she began gathering it up. Of 
course she could not have had much loose bark in her mouth and still 
cut more bark loose from the limb with her teeth. As usual she had 
done her work in the most efficient way. 
Many times I have offered my pet “flying” squirrels a tidbit that 
they preferred to the one they were eating. ‘This confronted them 
with a real problem. Their experience through the ages has been not 
to drop food, for it falls to the ground and is ordinarily lost. They 
usually solve the problem by looking for a place in which to cache the 
food they are eating, then come back to me to take what I am offering. 
Likewise I have many times put the same problem or a similar one up 
to the gray squirrels (Sciwrus carolinensis) of the eastern United 
States. Most of them try to solve it by attempting to take the second 
morsel without dropping the first. Usually they cannot do this but 
make several attempts and finally finish by sitting nearby to eat the 
first piece and then come for the second, or sometimes they give up 
the attempt and take the first piece home or at some distance to eat, 
then return for the second. When I am giving them peanuts in the 
shells there is often an amusing struggle to get two together in the 
mouth so that they can both be held. Sometimes a squirrel will hug 
the nuts in its arms next to its neck and take a few short hops to get 
away and work on them at its leisure. I saw one old lady squirrel 
develop an ingenious method of solving the problem. After working 
with the nuts for a few seconds on several occasions she sat there and 
shelled one of the nuts, put the kernels in her mouth, then picked up 
the other nut quite easily. Later another learned this method and 
