MICROSCOPIC FORMS OF VEGETABLE LIFE. 



261 



before this granular lining is formed. The rate of the movement is af- 

 fected by anything that influences the vital activity of the Plant; thus, it 

 is accelerated by moderate warmth, whilst it is retarded by cold; and it 

 may be at once checked by a slight electric discharge through the plant. 

 The moving globules, which consist of starchy matter, are of various 

 sizes; being sometimes very small and of definite figure, whilst in other 

 instances they are seen as large irregular masses, which appear to be 

 formed by the aggregation of the smaller particles. 1 The production of 

 new cells for the extension of the stem or branches, or for the origination 

 of new whorls, is not here accomplished by the subdivision of the parent- 

 Em- 15*. 



Generative organs of Charafragilis:^, antheridium or 'globule ' developed at the base of pis- 

 tillidium or 'nucule;' B, nucule enlarged, and globule laid open by the separation of its valves; c, 

 one of the valves, with its group of antheridial filaments, each composed of a linear series of cells, 

 within every one of which an antherozoid is formed; in D, E, and F, the successive stages of this 

 formation are seen: and at G is shown the escape of the mature antherozoids, H. 



cell, but takes place by the method of out-growth (Fig. 153, B, e, f s g, h), 

 which, as already shown ( 252), is nothing but a modification of the 

 usual process of cell- multiplication: in this manner, the extension of the 



This interesting phenomenon may be readily observed, by taking a small 

 portion of the plant out of the water in which it is growing, and either placing it 

 in a large Aquatic box ( 122) or in the Zoophyte-trough ( 124), or laying it on the 

 glass Stage-plate ( 120) and covering it with thin glass. A portion of Chara or 

 Nitella placed in the Growing-slide ( 121) may be kept under observation for 

 many days together. 



