GLIMPSES INTO PLANT STRUCTURE 33 



celled algae, known to botanists as Protococcus 

 viridis. Fig. 21 shows a magnified photograph 

 of this green stuff off my finger-nail, under a 

 medium magnifying power, and reveals a con- 



Fig. 21. The green stain on damp fences, &c., is composed ol 

 myriads of microscopic plants 



glomeration of granules, each granule a plant. If 

 we examine one of these green granules under 

 very high magnifying powers, we find that it 

 possesses considerable structural detail, simple, 

 perhaps, compared with the structure of the higher 

 plants ; but then it must be remembered that 

 these tiny living plant-atoms occupy only about 

 one-thousandth of an inch of space. 



c 



