BATS. 
227 
before they could eat. This waking would sometimes take as 
long as a quarter of an hour. I have observed the process care- 
fully ; it is always the same. The bat when thoroughly asleep 
is cold, dead cold to the touch. If I then took it in my hand it 
would not attempt to move about or seek for food, but lie 
quite still. On putting it to my ear I could hear a throbbing 
begin, at first very slowly and not very regularly, more than a 
second between the beats. Gradually the throbbing became 
quicker and quicker until it was impossible to count the beats, 
at the same time the warmth of the body was increasing very 
rapidly, and the bat quivering visibly. At last the throbbing 
becomes a continuous whirr, not unlike the purring of a cat, and 
the body feels quite hot to the hand. Then, rather suddenly, the 
throbbing quiets down like water coming to the boil, it slows 
somewhat, and becomes almost inaudible. The bat coughs or 
sneezes, chatters a little with its teeth, and begins to move about 
expecting to be fed. 
It would be interesting to know whether this throbbing is the 
beating of the heart, or some other muscular action. 
Hibernation. — The three bats of 1890 I set to hibernate 
on the 25th of November. I took them into an unoccupied 
room, where there would, as a rule, be no fire or gas burning. 
The weather shortly turned very cold and the winter was severe ; 
they did not seem to go very sound asleep ; I often found that 
they had changed their position in the box. I gave them no 
food. The long frost broke on the 21st of January ; on the 24th 
I took the bats into the sitting-room. I found that two of 
them were dead. Both were hanging head downwards, in the 
same position as if alive. Of one, the points of the wings and 
of the ears were withered ; of the other, only the points of the 
^vings. 
I warmed the living bat in my hand, and gave it part of a 
mealworm, which it eat sleepily. I then gave it some water 
to drink, and put it back into the box. After a while it began to 
move about ; so I took it out and offered it another worm, which 
it refused, but drank a lot of water. When put back it began to 
clean itself and stretched out each wing. Later in the evening 
it began to run about vigorously, so I gave it three mealworms, 
which it eat readily, and some more water. About midnight the 
bat was again restless ; so I gave it one more worm, a very large 
one. When I went to bed the bat was still at its toilet, paying 
special attention to the points of its wings. 
Next evening I tried whether the bat had at all lost its power 
of flight during its hibernation. The first flight it went once 
round the room and settled on a curtain ; the second flight four 
or five times round. The third flight it kept up so long that I 
grew tired of waiting for it to settle. The bat appeared to be 
perfectly strong ; its fur was in good condition, and it fed well. 
It lived till February 17th, when it was found dead on the 
bottom of the box. I could not discover the cause of its death. 
