ALG/E. 127 



actively for a few minutes. After a little time they 

 become motionless, lose their cilia, and develop into 

 many-angled cells, with the angles prolonged into 

 hornlike appendages. Under favourable circum- 

 stances, within a few days, the bright-green endo- 

 chrome begins to undergo change, and is soon 

 differentiated into gonidia, which unite within the 

 parent-cell and form a miniature net, in the same 

 manner as the large gonidia have been seen to 

 combine in the original water-net cell ; and, in due 

 time, this young net is set free by the dissolution of 

 the wall of the parent-cell. Thus a new individual is 

 formed from and within the resting cell in the spring, 

 in the same manner as the young nets are produced 

 by the large gonidia in the cells of the mature nets in 

 the autumn. And thus the cycle is complete. 



Green Volvox. 



"A thing of beauty is a joy for ever," and such is 

 the little organism so well known to all lovers of 

 pond-life as Volvox globator (Fig. 25). Quiet pools and 

 clear ponds in woods and on commons often swarm 

 with them ; ever turning, rolling, floating in perpetual 

 motion. Little green spheres, sometimes no larger 

 than the head of a good-sized pin, seldom so ample 

 as a small pea, must have their beauties revealed 

 under a microscope, and hence, to the multitude, 

 their very existence is unknown. Seen under favour- 

 able circumstances they are found to be spherical 

 in shape, covered apparently by the most delicate 

 network, as of the finest cobweb, with little green 

 points scattered all over the surface, and yet so 



