30 CHARLES F. W. MC CLURE 



pi a nation of this is that at this stage more free water is 

 generally being added to the lymph in the subcutaneous lymph 

 sinuses than can simultaneously be transported to the kidneys 

 through the agency of the heart and systemic blood vessels. 

 Lymph therefore gradually accumulates in the subcutaneous 

 lymph sinuses of the body, while formerly its accumulation 

 was regulated and controlled by local conditions. As stated 

 above, the oedematous condition of the body which results 

 when dead frogs remain in water is owing to the fact that, 

 while water still continues to be transported through the 

 integument into the subcutaneous lymph sinuses, all means 

 of transportation to the kidneys by the vascular system has 

 been discontinued. In advanced stages of red-leg disease, 

 cardiac inefficiency similarly acts as a leading factor in ren- 

 dering it impossible for as much free water to reach the 

 kidneys and to be excreted by them as simultaneously enters 

 the subcutaneous lymph sinuses through the integument, so 

 that lymph generally accumulates in the body in excess of 

 what experiment has shown us to be normal. 



Up to this point we have considered certain causes which 

 may account for the occurrence of localized and generalized 

 oedema commonly associated with red-leg disease. We have 

 found also that in frogs whose legs or ureters have been 

 ligated, the resulting subcutaneous oedema is accompanied 

 by an intracellular (interstitial!) oedema; the same is the 

 case in red-leg disease. We, therefore, come now to an analy- 

 sis of the behavior of muscles from frogs with red-leg dis- 

 ease, under experimental conditions similar to those used in 

 our study of muscles from frogs whose legs or ureters had 

 been ligated. 



Should oedema of muscles in red-leg disease be due to an 

 osmotic reaction, we should predict that muscles of a normal 

 healthy frog would gain in weight when immersed in lymph 

 obtained from a frog with red-leg disease; and, conversely, 

 that the muscles of a frog with red-leg disease would lose in 

 weight when immersed in a Ringer's solution, isotonic with 

 normal resting muscle. The reason for this would be that 



