yo Researches Regarding Cholera : The Blood. [part i. 



The bioplasts may frequently be observed at the edge of the rim of serum crawling 

 along it, and, as it were, moulded to the curve of the marginal fluid (Fig. 3). 



The period of extreme activity varies considerably, but, as a rule, at the close 

 of twenty-four hours from the commencement of the observation, only a few remain 

 freely motile, and the majority have considerably increased in size (Fig. 4). Towards 

 the close of the freely moving, amoeboid period, the density and refractiveness of the 

 bioplasts increase, and there is an increase in the number and distinctness of the 

 granules contained in their substance. Many, too, in place of remaining uniformly 

 granular, begin to show a tendency to the formation of one or more nuclear spaces 

 or vacuoles (Fig. 4), which appear as bright spots surrounded by more or less defined 

 circles of granules. As the movements of the bioplasts diminish, this vacuolation 

 increases in distinctness, and is very well marked when they have fairl}^ ceased, 

 which they do very gradually ; changes in form persisting for some time after the 

 cessation of free locomotion. As the movements cease, the majority of the cells also 

 assume a more or less rounded form, a few only becoming fixed with irregular or 

 . lobed outlines, and contemporaneously they tend to accumulate in heaps and masses 

 of varying extent (Fig. 4). 



The preparation in this stage shows a multitude of irregular masses, composed 

 of bodies which vary considerably in size, and which in refractiveness and general 

 aspect closely resemble pus-cells in which the vital movements have ceased. The 

 vacuoles are now very distinct and well defined, and the entire body has a denser, 

 " plumper " appearance than it ever had before. 



Whilst these phenomena have been taking place the serum remains quite clear 

 and free of bacteria or monads, and the only change which occasionally occurs 

 in it is a certain amount of staining, due to the escape of colouring matter from the 

 corpuscles as the clot begins to soften. The preparation having reached this stage 

 may remain unchanged for weeks, the serum continuing perfectly fluid and clear 

 throughout, but in the majority of cases, the bioplasts pass on to further changes. 

 The exact nature of these changes varies greatly in individual preparations and in the 

 individual bioplasts of the same preparation. The bioplasts may gradually break 

 up and disintegrate, filling the serum with molecular flakes, which for some time 

 show indications of the outlines of the individual masses with more or less distinctness, 

 but ultimately become uniform. Such flakes might very readily be described as 

 flakes of monads, and be supposed to arise by aggregation, had the processes by 

 which they are formed not been followed out. This may be regarded as the simplest 

 method of termination of the bioplasts, but there are others which are more complex, 

 and which, inasmuch as they give rise to very different appearances in individual 

 specimens of blood, must be clearly distinguished and described. In many instances 

 there appears to be a certain condensation of substance around the vacuole or vacuoles 

 so as to leave a more fluid ring between this condensed portion and the outer 

 margin of the bioplasts, which at the same time assumes more or less clearly the 



