100 J. W. JENKINSON. 



whole cell contents, would produce a form quite similar to that of 

 Uiococcus, except that it would be multinucleate and possess 

 no starch grains. 



Two or more cysts are often found in the same Sphagnum 

 cell. These by their growth exert a pressure upon one another, 

 which may result in the death of one of them, or in the 

 bursting of the Sphagnum cell, and consequent protrusion 

 of the cyst. This mutual pressure also occurs in any cysts 

 which happen to lie closely together, producing thickenings of 

 their walls where they rest on one another. This latter also 

 occurs in solitary cells. The completely grown cysts contain 

 at least eight nuclei, sometimes as many as thirty-two. 



The number of chromatophores, their size and distribution, 

 are extremely variable. The quite young cysts generally contain 

 few, but those large ; the full-grown cysts much smaller ones, 

 but in very much greater numbers. In the ripe cysts they can 

 only be distinguished from one another by squeezing out the 

 contents ; but if the cyst be unripe there are numerous large 

 vacuoles in the protoplasm, which make it quite possible to see 

 the separate chromatophores as well as the minute crystals of 

 calcium oxalate with which the vacuoles are crowded. 



The over-production of this calcium oxalate seems to be in 

 some way deleterious to the organism; if the cell contents 

 migrate the crystals are egested, but the amoeba stage may be 

 altogether prevented by their presence. If the organism be kept 

 in lime water calcium oxalate is produced in excessive quan- 

 tities, and many cysts are killed ; the chromatophores are the 

 first to die, being transformed directly into brown or blackish 

 masses, and after them the nuclei become disorganised. 



The vacuoles mentioned above as occurring in the unripe 

 cvsts may run into one another. The protoplasm is then 

 divided up into numerous rounded or angular portions, each 

 containing a nucleus, and termed originally by Sachs (10) an 

 " euergid.^' They are connected with one another by threads of 

 hyaline streaming protoplasm, along which are carried the 

 glistening physodes (Archer's spindles), and sometimes chro- 

 matophores as well, but never nuclei. The separation of the 



