764 
Journal of Agricultural Research 
Vol. XXXI, No. 8 
At. 3.55.—Regular respiratory movements commenced, accom¬ 
panied by muscular movements of legs and back. Animal straight¬ 
ened out. Hitherto she had been lying on her side, trembling like a 
new-born lamb, and apparently unconscious and helpless. Now her 
front limbs were shaking like one with the ague, while the hind limbs 
were perfectly still. 
At 4.05.—She was gasping for breath. 
At 4.10.—Violent shaking of the front paws, with a straightening 
out of the body. There was still little motion of the hind limbs. 
At 4.22.—She was able to maintain a position on her belly, attempt¬ 
ing to crawl. Eyes still shut. 
At 4.25.—Rapid heart beat noticeable. For the first time the 
muscles began to be resistant. There was quite a tenacious grip in 
the toes. The tail was controlled by muscular movements. She 
responded nervously when touched. 
At 4.33.—Squirrel was very warm and comfortable, and well able 
to crawl about. It was now difficult to keep her in front of the camera. 
One very noticeable feature was the very great acceleration in the 
awakening process, beginning at 4.25 and terminating with the 
almost completely wide awake condition at 4.50. 
Three other squirrels were studied, and in each case similar observa¬ 
tions were made. In all of these it was noticed that the posterior 
part of the body remained inactive and lifeless much longer than the 
anterior. These observations were made independently, but later it 
was noted that a French experimenter, Mares, 3 showed by injecting 
ground squirrels that the circulation in the posterior part of the body 
was largely suspended during hibernation and that this part of the 
body was the last to come from that condition. 
That they regain fleetness and acutenss of their senses in a short 
time is shown by the following incident: On November 18 a squirrel 
was dug from hibernation two days before it was taken back to its 
den to be photographed. Suddenly it made a dash for liberty and 
darted into a very obscure hole beside a fence post, about 3 rods 
from its den, seeming to be familiar with the surrounding territory 
and in keen possession of its senses. 
Interesting observations were made during the winter in regard 
to daily weight losses and the duration of hibernation. The records 
are given in Table I. This table shows a rather constant loss of about 
1 gram a day for both the Columbian and Townsend squirrels. 
Table I .—Weight losses, in grams , of jive squirrels during winter hibernation 
Species 
Weight 
when 
going 
into 
hiber¬ 
nation 
Weight 
when 
coming 
out of 
hiber¬ 
nation 
Total 
weight 
lost 
Dura¬ 
tion of 
hiber¬ 
nation 
in days 
Amount 
lost per 
day in 
grams 
C. c. columbianus male No. 8.. 
592 
530 
62 
63 
0.98 
C. c. columbianus male No. 9__...._ 
445 
394 
51 
28 
1.8 
C. c. columbianus female No. 7___ . 
414 
273 
141 
77 
1.8 
C. c. columbianus female No. 8... 
500 
370 
130 
119 
1.09 
C. townsendi male No. 5.._. 
280 
221 
59 
56 
1.05 
3 MarEs, F. experiences bur l’hibernation des mammifEres. (M£moire) Compt. Rend. Soc. 
Biol. [Paris] (s6r. 9, t. 4) 44: 313-320. 1892. 
