444 TOKUYASU KUDO 



penis was extruded, possibly from attempts to get the urine. It 

 is to be noted that the specific symptoms generally found associ- 

 ated with various vitamine deficiencies are either slight or entirely 

 absent in survivors of these thirst experiments. 



The general condition observed at autopsy are as follows: 

 There is extreme general emaciation, especially in the longer peri- 

 ods. The skin and muscles appear somewhat dry and difficult 

 to separate. The blood is thick. The fat has usually almost 

 disappeared from the subcutaneous and muscular tissues; but 

 in some cases it remains in relatively large amount. The orbital 

 and interscapular fat persists in small amount even in the longer 

 experiments. There is no appreciable change in amount of serous 

 fluid in the pericardial, pleural, and peritoneal cavities. The 

 viscera generally appear normal. The liver is often congested 

 and occasionally yellowish in color (fatty change?). The kidneys 

 are often congested, and their surfaces appear rough in a few cases. 

 Marked congestion of the brain, kidneys, suprarenals, spleen, and 

 lungs was sometimes found. In general, however, the effects of 

 thirst on young rats, as shown by observations and autopsy, 

 appear slighter than in adult rats. 



LENGTH OF BODY AND TAIL 



The body length is measured from the tip of the nose to the 

 anus and the tail length from the anus to the tip of the tail. The 

 measurements were taken immediately^ after death, the body and 

 tail being extended by very slight tension. Measurements dur- 

 ing life are not very accurate, although they might be obtained 

 by the use of anesthetics. Some measurements were made on the 

 living animals, however, which show changes in the lengths of 

 body and tail similar to the changes indicated by the measure- 

 ments at autopsy. 



In the groups of rats held at constant body weight for the five 

 periods (table 2) the percentage changes in average body length 

 are insignificant, usually corresponding to the slight differences 

 in body weight between test rats and controls. It is evident that 

 the body length remains nearly constant. The tail length, how- 

 ever, shows a marked and progressive increase, indicating for the 



