LECT III. 



SKIN OF DIFFERENT REGIONS. 



59 



upon the substance of the membrane, and to the consecu- 

 tive alteration of structure. 



The diminution of the intensity of endosmose observed 

 with the skin of the torpedo, but only in the less favourable 

 position of the membrane, is confirmed, whatever may be 

 its position, by employing the skin of the frog; but this 

 decrease does not proceed regularly, as we may observe in 

 the following table, in which A and B represent the same 

 endosmometers as in the preceding table : 



Endosmose through the Skin of the Frog. 



During the night the liquid overflowed both the endos- 

 mometers, but there was no inversion of the current, as 

 had taken place with the skin of the torpedo. Neither 

 was this phenomenon observed with the skin of the eel, 

 even when the experiments were continued for more than 

 fifteen hours ; but the increments were irregular, as with 

 the skin of the frog. 



Skin of different Regions. It was important to determine 

 whether the force of endosmose varied when the skin was 

 taken'/rom different regions of the body. The experiments 

 made to ascertain this were not very numerous ; and we 

 shall content ourselves by saying that no difference was 

 observed in the current of endosmose, whether we used 



