414 TOKUYASU KUDO 



Eyeballs 



The occurrence of conjunctival congestion (or hemorrhage) and 

 the opacity of the lens were mentioned under 'General observa- 

 tions.' Conjunctival congestion during extreme human thirst 

 was noted by Tiedemann ('36) and conjunctival infection was 

 reported in the dog by Pernice and Scagliosi ('95). Opacity of 

 the lens in dehydrated frogs was noted in some cases by Durig 



Coi). 



As shown in table 2, the eyeballs in my acute-thirst series lose 



10.2 per cent in average weight, and in the chronic-thirst series 



13.3 per cent. In the rat (Si. 2), on total inanition, the apparent 

 loss of weight in the eyeballs is 13 per cent. In a dog on dry diet 

 with loss of 20.7 per cent in body weight, Falck and Scheffer ('54), 

 on the contrary, found an apparent gain of 19.7 per cent (proba- 

 bly due to an individual variation) in the weight of the eyeballs. 

 During inanition with water in the albino rat, no significant 

 change in the weight of the eyeballs was found by Jackson ('15), 

 who cites a few similar observations by previous authors. Bitsch 

 ('95) found the absolute weight of the eyeballs in the dog usually 

 increased during inanition, and suggested that it might be due to 

 edema. Possibly the lack of available water during thirst may 

 explain the decrease in the weight of the eyeballs in the present 

 experiments, but a further investigation on this point is required 

 before a final conclusion can be reached. 



Heart and aorta 



Heart. The heart in the acute-thirst series (table 2) shows a 

 loss of 30.6 per cent in average weight, and in the chronic-thirst 

 series a loss of 46.3 per cent. In the rat (Si. 2) , after total inani- 

 tion (table 1), the corresponding apparent loss is 42.6 per cent. 

 Since the heart during thirst loses somewhat less in weight than 

 does the body as a whole, it increases accordingly in relative 

 (percentage) weight. 



Few data in the literature are found concerning the weight of 

 the heart during thirst. Falck and Scheffer ('54) noted in the 

 dog a loss of 4 per cent in the heart and aorta, with a loss of 20.7 



