Ixx 



THE BEGINNINGS OF LIFE, 



quently by distortion in all directions, produce a mass whose 



be very difficult to determine, were it not 



ongm 



might 



of segmentation whilst still 



\ 



As these changes advance the units 



they have moved about for a time as Amcehce, they reassume 

 an ovoid form, and become covered with cilia, w^hich vibrate 

 actively. Further alterations have not been traced. 



7. The next change is one commencing in the so-called 

 ^ chlorophyll utricles/ which exist not only in the stems 

 and leaves of Mosses, but also in their closely-related radicles 

 and confervoid filaments. They are minute homogeneous 

 granules, or, perhaps more correctly, saccules. Nageli 

 had pointed out that they were provided with an outer 



^ For details concerning this metamorphosis, see ' Journ. of Microsc. 



Science/ April 1S62. ^ ^^y goc. 1849, PP- 1 76-178- 



\' in the - 



^^ they 1 



5 



that 



P 



oints 



. -p-^ 



:ated u 



nde 



confen 



generally possible to find some small part retaining the 

 original filamentous condition.' 



The other reproductive (?) changes described by Dr. 

 Braxton Hicks as occurring in the confervoid filaments of 

 Mosses are of a most remarkable character, and are perhaps 

 more intimately connected wdth a failing vitality of the 

 mother-cells than those hitherto described. They seem to 

 be instances of true heterogenesis. 



6. The whole of the contents of one of the cells may 

 gather together ' into one or more oval masses, which be- 

 come covered by a cell-wall thrown around each portion.' 

 Then two different kinds of changes may ensue. Either (a) 

 they may undergo a process 



within the parent cell, the products being ultimately liberated 

 by the solution of the cell-walls, containing and contained ; 

 or {b) the cells may gradually lose their green colour, and 

 assume a colourless appearance save for the presence of a • %! and, as th 



fc centre. Aft- 

 chloro^ 



ig^les at first bei 

 ;^saine time th^ 

 rJAs thev ir 



-§ 



r 



:;,an(iitwascle; 

 existence ' 



^IodIivU utricle: 



J 



■: 



Ikse CO 



se once 



few reddish granules. 



assume the appearance of veritable AmcebcE, possessing one or 



+ 



two contractile vesicles, and exhibiting the usual changes of '^efree. . . . Jj^ 

 form and movements characteristic of such organisms^ After ^and beina 



"^f residue of th 





r; and 



, as 



] ^*s of the ^ 

 I their suh 





, '"^ an ova 



'ii 



\. 



or 





eybe 

 even 



:\ 



chl 



At 



orop: 



I 



»1 



