136 



THE SNOW-PLANT. 



Fig. 77. 



Fie. 79. 



the Confervse) swells to a larger size, (fig. 74, c,) and the two 

 granular masses, (g-,) increasing in transparency, become grad- 

 ually tinted with a light green, whilst one end of each changes 

 to a clear transparent area (e) totally devoid of granules, and 

 the nucleus (n, n l ) enlarges considerably, and at the same time 

 loses all of its color.* Frequently before these changes occur 

 the two granular masses of the primary stage (fig. 73, g; g" 1 ) 

 divide again, each doubling itself and its nucleus, and then the 

 changes of their color and of the nucleus, which I have just 

 described, occur. 



In this figure (fig. 75) the four masses, (g 1 ,) the future spores, 

 have already assumed their final shape, and the narrower end 



Figs. 73 to 79. Prolococcus pluvialis. The successive phases of growth of 

 the plant from the resting stage to maturity, c, the cell-wall ; g,g ] , the granular 

 cell contents ; n, n 1 , the nucleus ; e, e 1 , the transparent end of the cell ; e 2 , the 

 transparent centre ; I, the vibratory lashes. Original. 



* Jt is barely possible that the nucleus disappears as the transparent space 

 develops. 



