16 CHARLES P. W. MC CLURE 



been found to be the case with lymph taken from the sub- 

 cutaneous lymph sinuses of the leg of a frog in which an 

 oedema has been experimentally produced as the result of 

 ligation. 



The legs of three large bullfrogs (R. catesbiana) were li- 

 gated near the thigh, and the frogs were placed in water. At 

 the end of forty-eight hours, 30 cc. of bloody lymph was re- 

 moved from the subcutaneous lymph sinuses of the legs of the 

 three frogs and 30 cc. of clear straw-colored lymph was ob- 

 tained from the coelom (ascites) of one of the three. 



The A or freezing-point depression of this lymph, as well 

 as its hydrogen-ion concentration, were kindly determined 

 for me by my colleague, Doctor Marshall, of the Department 

 of Physical Chemistry. They were as follows : 



Leg lymph, obtained from three frogs, A = 0.394° — pH, 4.97 

 Coelom lymph, obtained from one frog, A = 0.368° — pH, 7.60 



The freezing-point lowerings are correct within 0.005 of a 

 degree. 



From the above determinations it is evident that the os- 

 motic pressure of lymph obtained from the oedematous area 

 is lower than that of Ringer's solution (A =0.445°) which 

 has been found to be approximately isotonic with the resting 

 muscle of a normal frog. 



The following type experiments tabulated in tables 3 and 4 

 fully bear out the views previously expressed — that the rest- 

 ing muscle of a normal frog (table 3) should gain weight 

 when immersed in lymph obtained from the subcutaneous 

 lymph sinuses of an oedematous area, and that an oedematous 

 muscle (table 4) should lose weight when immersed in 

 Ringer's solution, approximately isotonic with resting muscle 

 taken from a normal frog. 



The type of experiment shown in tables 3 and 4 has been 

 repeatedly made on frogs of different species and with lymph 

 taken at different times from different frogs. We therefore 

 believe it may be stated that the differences in weight of the 

 muscles observed in these experiments result from differ- 

 ences in osmotic pressure which exist in the intermuscular 



