^/f^. 



It] 



y '^^^ V. 



T of 



Such 



not !- 



K 



'^. 



IS to be 



of the embr 



'^0 small and ir 

 This segmeolit 

 'ourless portio:; ' 

 ; more cental p 

 :te decolourizat:: 



r 



on. Sometk;:. 

 the transformit: 



I 



.r^and then it - 

 i\ lonads kf 



ev 



I 



elopnient 



e by one. ^-'^ 

 ter layer is 



ts has 



been 



...I 



en in 



i> 



* ifi ^ 



jp 



luring 



their «'- 



ins 



tances 



I 



i^ 



e 



mai"^ 



a r»^' 





(re 



ic 



cban^' . f 



ther 



sphef' 



'.rsio^' 



T/I£ BEGINNINGS OF LIFE. 



403 



4. The supervention of less favourable conditions 

 during the progress of the last-mentioned change will 



Fig. 79. . 



Lower Transformations of the substance of Nitella. ( X 600.) 



a, a', Amceboid masses of different sizes, densely packed with bright- 

 green chlorophyll corpuscles. 

 J. A similar mass after decolourization — constituting an ' em- 



bryonal sphere.' 



c. 



An embryonal sphere segmenting into Monads (c'), but leaving 



a dark-coloured refuse-heap. 



fl?, e,/. Three interchangeable developments of smaller embryonal 



spheres: d, a sporangium giving birth to an arborescent 

 outgrowth; e, a sporangium which subsequently segments 

 into Monads ; /, a large kind of Pythium which subsequently 

 develops its usual blind tiibe (/). 

 Three forms of Sporangia which are occasionally formed from 

 the central portions of embryonal spheres. 



K^ g\ g"^ 



No 



put a stop to it^ and cause change 



In this case^ whilst the peripheral portions of the 



Monads 



D d 2 



