PAPERS ON ZOOLOGY AND PHYSIOLOGY 333 
intense, such as the heart and central nervous system, preserve 
themselves best while the organs in which metabolism is less in- 
tense waste away. The preservation of the working tissues is 
thought to be brought about by the autolysis of the other less 
active tissues. The products of autolysis of these less active 
tissues pass into solution in the blood, are carried to the mastex 
tissues and used. The object of this investigation was to 
determine what change, if any, occurs in the catalase content of 
the heart, skeletal muscles and fat during starvation with the 
hope of finding an explanation for the fact that the heart 
muscle is not autolyzed during starvation while the skeletal 
muscles and fat are. 
Twelve rabbits were placed in a cage and fed for six days on 
cabbage, turnips and apples. At the end of this time two of 
the rabbits were etherized and the blood vessels washed free of 
blood by the use of large quantities of 0.9 per cent sodium 
chloride. The heart, soleus muscle (red muscle) and fat 
around the kidney were removed and ground up separately in 
a hashing machine. The catalase content of these tissues was 
determined by adding one gram of the material to 45 cc. of hy- 
drogen peroxide in a bottle. As the oxygen gas was liberated 
it was conducted through a rubber tube into an inverted bur- 
ette previously filled with water. After the oxygen gas thus 
collected was reduced to standard atmospheric pressure the re- 
sulting volume was taken as a measure of the amount of cata- 
lase in one gram of the tissue. The catalase content of the 
heart, soleus muscle and fat of rabbits starved for two, four 
and six days respectively was determined as it had been for the 
normal rabbits. The results of these determinations are given 
in table 1. Each of the determinations represents an average 
for two animals. 
TABLE 1. 
After heart, leg and fat are given the amounts of oxygen in cubic centi- 
meters, liberated in ten minutes from 45 cc. of hydrogen peroxide by 
the catalase in 1 gram of the respective muscles of rabbits. 
| | Starved | Starved | Starved 
Rabbits | Normal | Two days 
Four days} Six days 
LEE AN Bee POD 0S Coan eae een ee | 33 | 13 | 12 | No fat 
Paear ee age eles 73 | 71 75 75 
| Ag BU AA | 72 58 54 44 
It may be seen in table 1 that one gram of the heart muscle 
of the normal rabbit liberated 73 cc. of oxygen in ten minutes 
