404 DAVID E. FINK. 



comparable with the oxygen consumption of starving animals. 

 A reduced CO2 output occurs throughout the progress of hiber- 

 nation. 



3. Preparation for hibernation follows a period of extensive 

 feeding and consists in an accumulation in the adipose tissues of 

 29 per cent. fat. During prehibernation a reduction of the water 

 content of 20 per cent., the elimination of waste products from 

 the digestive tract and a lowered metabolic activity of the 

 animal take place. 



4. The greatest depletion in fat occurs during the first few 

 months of hibernation. In the metabolism of the fat body, the 

 fat is replaced by albuminoid granules and other products. 

 Sections of adipose tissue before and after hibernation are 

 comparable to sections of the hibernating gland of mammals. 



5. The respiratory quotient is lowest during the first few 

 months of hibernation and highest at the termination of dor- 

 mancy (0.60-0.76). In hibernating animals possessing insuffi- 

 cient nutriment and in starving animals, the respiratory quotient 

 is exceedingly low (0.54). There appears to be a parallelism 

 between a rapid depletion of reserve food and a low quotient. 



6. Recovery depends upon the length of time potato beetles 

 spend in hibernation. It is more rapid with those in hibernation 

 for the longest time. Actual contact of the animal with water 

 seems necessary to restore its water content before feeding 

 is possible. 



7. Catalase activity of hibernating beetles is greatly reduced 

 and their total catalase content is lower than that for old or 

 young active beetles. There appears to be a correlation between 

 the reduced catalase activity and diminished respiratory meta- 

 bolism in hibernating and starving animals. 



Although active beetles give very striking oxidase reactions, 

 no characteristic blueing of guaiacum was obtained with any 

 organ, tissue, or body fluid of hibernating forms. 



BIBLIOGRAPHY. 

 i. Baumberger, J. P. 



'14 Studies in Longevity of Insects. Ann. Ent. Soc. Amer., VII., 323. 



2. . 



'17 Hibernation: A Periodical Phenomenon. Ann. Ent. Soc. Amer., X., 179. 



