EFFECTS OF THIRST — ALBINO RATS 407 



previously they were very tame. Mental disturbance has also 

 been noted in men during extreme thirst (Tiedemann, '36; Zaba- 

 ver, '04). The rat (Si. 2) subjected to total inanition ate about 

 half of its tail during the experiment. In the chronic-thirst 

 series, the rats always had the penis extruded, possibly from 

 attempts to get the urine. 



The general conditions observed at autopsy are as follows. 

 There is extreme general emaciation. The skin and muscles ap- 

 pear dry and are difficult to separate. The blood is very thick. 

 The fat has almost disappeared from the- subcutaneous and mus- 

 cular tissues, but persists in small amount in the orbit. The adi- 

 pose tissue of the interscapular region is reduced to a small, 

 brownish-red mass. A small amount of serous fluid is found in 

 the peritoneal, pleural, and pericardial cavities. The appearances 

 of the brain, spinal cord, lungs, and abdominal viscera will be 

 mentioned later in discussing the individual organs. 



BODY WEIGHT 



As shown in tables 1 and 2, the average initial gross body weight 

 of eight rats in the acute-thirst series is 218.8 grams and in the 

 three controls, 218.3 grams. The loss in body weight in the 

 acute-thirst series averages 36.1 per cent, the loss in individual 

 cases ranging from 31.8 per cent to 45.9 per cent. This represents 

 nearly the maximum possible loss during the acute-thirst experi- 

 ments, as the rats were killed only in very advanced stages of 

 inanition. Three other rats of 152, 162, and 208 grams that were 

 fed small amounts of milk (average 3, 2, and 2.8 grams daily) 

 died with losses in body weight of 33.8, 31.6, and 35.7 per cent, 

 respectively. These rats have been excluded from the tables, as 

 previously explained. In the rat (Si. 2) on total inanition, the 

 body weight decreased from 216 grams to 114 grams, a loss of 

 47.2 per cent in eleven days, at the end of which time the rat 

 was killed. 



These losses in total and acute water inanition are greater than 

 those obtained by Jackson ('15) in acute inanition with water. 

 In a series of fifteen albino rats, he obtained an average loss of 

 33.1 per cent (range 25 to 40 per cent) in an average of nine (six 

 to twelve) days. 



