PLATE LX. 



Figures magnified 500 diameters. 



Page. 



Fig. 1. Phymatodouis Nordstedtianum, . . . 28 



" 2. " " a cell dividing, . . 28 

 Figs. 3, 4. " " transverse view, and front 



view of a cell, . 28 

 Fig. 5. Desmidium {Didymoprium) quadratum, front and side views 



made evident by the 



twist of the filament, 26 

 " 6. Desmidium (Didymoprium) longatum, front and side views of 



cells, . . .27 



" 7. Desmidium aptogonium, partially advanced in process of di- 



vision. (Compare normal condition, 



Plate II, fig. 6), . . 27 



" 8. Sphaerozosma pulchrum, Var. inflatum, ... 29 



" 9. Sphaerozosma rbctangulare, .... .31 



" 10. Calocylindrus pseudoconnatus, Var. (Compare Plate XV), 60 



" 12. CoSMARiUM OBSOLETUM, Var. major, . . 70 



" 13. COSMARIUM SEXAN60LARE, . . 69 



Figs. 14-17. COSMARIUM QLOBOSUM, . . 63 



Fig. 18. CoLOCYLiNDRUs CONNATUS, Var. minor, . 60 



" 19. COSMARIUM Kjellmanu, . 94 



Figs. 20, 21. " " end and side views, 94 



Fig. 22. Cosmarium ornatum, Var. protractum, . . 90 



Figs. 23, 24. " " front and side views, 90 



Fig. 25. Cosmarium pulcherrimum, Var. minor, . . 97 



Figs. 26, 27. " " side and end views, . . 97 



Fig. 28. Cosmarium Sportella, ..... 90 



Figs. 29, 30. " " lateral and vertical views, 90 



" 31, 32. Cosmarium crenatum, .... 73 



