PLATE II. 



Figures magnified 500 diameters. 



P \r,F. 



Figs. 1,2. Desmidium Swabtzh. Two forms; filaments in vegetative con- 



dition, . . .26 



Fig. .".. Filament in fruit : the spores, ami empty 



cells forced apart by the growth of the 

 spore, ..... 26 

 Figs. 1, -i. End view of cells, showing tin- triangular 



form of tin- filaments, . . 26 



Fig. 6. Desmidium Aptogontum, a vegetative filament, . . . 27 



" 7. tin- triangular end view of the same, 27 



FigB. 8, 9. Desmidium Baileyi. (Aptogonum Baileyi.) 8. the normal vege- 

 tative condition of tin- chlorophyl : '.*. the 

 same concentrating for tin- formation of 

 thr spores, . . -7 



Fig. 10. " the fully developed spores, . . 27 



" 11. spores matured and separating from I lie 



filaments, . . . . .27 



Fig. 12. end view <>l filament, . . . 27 



' 1-".. Desmxdium quadrangui \ tum : part of a filament, . . 27 



14 " ' end view of filament, . 27 



