( 11« ) 



also exhibit contriictioii by liyperisotunic uiul expau.siou by liypiso- 

 tonic solutions. 



2. The observation, that the amount of this expansion and con- 

 traction is much less than it would be if the cells in question 

 consisted of a homogeneous mass, leads to the conclusion, that the 

 cells must consist of two substances, one representing the hygi-os- 

 copic power of the cell, the other, which has no share, or only a 

 slight one in the hygroscopic power. 



3. By the quantitative determination of the expansion and 

 contraction which the cells undergo under the influence of NaCl- 

 solutions of different concentrations, or of serum, mixed with dif- 

 ferent quantities of water we have a means of fixing the percentage 

 proportion between the two constituents of the cells. 



From the experiments hitherto made it has appeared, that in the 

 white blood corpuscles of the horse the volume of protoplasm-sub- 

 stance amounts to 56.77o — 53.7% 

 For the red corpuscles of the horse 55 % — 53 "/^ 

 „ „ „ „ of the rabbit 51 0/^^—48.7% 

 » « . r, of the frog 76.47o-72 "/o 

 „ „ spermatozoa of the frog 79.47o— '73.2"/o 



If we injure the white bloodcorpuscles by mechanical means, 

 the expansion and contraction under the influence of salt solutions 

 appears to be almost unchanged. The results obtained are with 

 difficulty otherwise to be explained but by supposing, that these 

 cells consist of a network of protoplasm, the closed meshes of which 

 contain a fluid that exclusively represents the hygroscopic power of 

 the cell. 



Consequently BüTSCHLi's theory of the „Wabenstructur" of the 

 cells receives, at least for the leucocytes, from physiological experi- 

 ments a powerful support, which seems not to be superfluous in 

 face of the objections of an histiological nature which have been 

 urged against the arguments in its favour. 



(October 14th 1898). 



