LIST OF ILLUSTRATIONS 



I. 



2. 



3' 

 4' 

 5- 

 6. 



7- 

 8. 



9' 



10. 



1 1. 



12 



13- 

 14- 

 15- 

 i6. 



17- 

 i8. 

 ig. 



30. 

 31. 

 22. 

 23- 

 ^4- 

 25- 

 26. 



Transverse section of beech twig . . . Frontis/>icce 



Unicellular plants multiplying 



Desmids {Closteriuiii lunula) . 



Desmids {Micrasterias denticulata) 



Diatoms grouped 



Diatoms on a darl;; ground 



Diatoms dredged from the Atlantic 



Diatoms common in ponds and lak' 



Diatom-chains 



Selected diatom {Arachnoidiscus Ehrenbcrgii) 



Central portion of diatom group, Fig. 4 



Selected diatoms from group, Fig. 10 . 



Selected diatoms from group, Fig. 4 



Artistic arrangement of diatoms 



Central portion of diatom group, Fig. 13 



Another artistic arrangement of diatoms 



Central portion of group. Fig. 15 . 



Thread-like plants {Spirogyra) 



Volvox globatov .... 



Freshwater alga (Draparnaldia) 



Freshwater alga (Batracliospervuiin) 



Alga on damp fence 



Vegetable cells of apple . 



Hairs from flower of pansy 



Cells from surface of geranium petal 



Scales from fern frond . 



Vascular tubes in stem of bracken fern 



3 

 5 

 7 

 10 

 12 

 14 

 15 

 i6 



17 



18 



19 

 20 

 21 

 23 

 24 

 26 

 28 

 29 

 30 

 31 

 33 

 35 

 37 

 38 

 39 

 40 



