LEO LOEB AND KENNETH C. BLANCHARD. 



than in others. It also depends upon the solution by which these 

 cells are surrounded. In neutral solutions of sodium chloride the 

 large majority of the cells have lost their granule stain within the 

 first 24 hours. But in addition to the granule stain there is a 

 second state in which the stain is found in the cell. It appears in 

 the form of droplets or particles which are usually situated more 

 centrally than the majority of granules, many of which are 

 located in the peripheral part of the cell. Often more than one 

 droplet or particle is present and the size of these droplets varies 

 in different cells. In these droplets or particles the stain is 

 retained much longer than in the granules. They resist also the 

 decolorizing effect of acid more successfully than do the granules. 

 They may persist for some time even after the cells have disinte- 

 grated and in such cases they indicate the place where cells have 

 perished. The stain must therefore be fixed much more firmly in 

 these droplets than to the granules. The variations which we 

 find in the number and size of these droplets and particles make it 

 probable that these drops represent cell vacuoles, rather than 

 definite organs, although, if the latter should be the case, it would 

 not alter our conclusions. It is probable that a certain surplus of 

 stain, which cannot be held by the granules, is eliminated into cell 

 vacuoles. In hyaline cells this is the only state in which the 

 stain is found. These droplike formations in which the stain 

 occurs in amoebocytes have some similarity to the droplike 

 formations in which vital stains of an acid character are found in 

 certain kinds of cells. However, such an acid stain, as trypan- 

 blue, does not seem to be taken up to any noticeable extent by 

 amcebocytes. 



2. In order to reach the granules the basic neutral red must 

 pass through the outer cell boundary and through the hyaloplasm. 

 In the case of neutral red the cell protoplasm (hyaloplasm) proper 

 is not stained, but certain other basic dyes may perhaps cause a 

 very light diffuse stain. A diffuse stain has been definitely 

 observed in infusoria. 



As to the reason why in most cases the protoplasm does not 

 stain under those conditions, we may assume that the affinity of 

 the dye for the granule substance is much greater than for the 

 intergranular protoplasm. In addition it has been assumed that 

 processes of reduction may make the dye invisible in the cell. 



