SPIROGYRA 133 



31. Diameter vegetative cells more than 



60 /x 33- ^- g<illi(^^ 



31. Diameter vegetative cells less than 60 p- 32 



32. Diameter vegetative cells usually 



40-50^1, median spore wall yellow 35. S. porticalis 



32. Diameter vegetative cells 38-44 /a, 



median spore wall yellow-brown 34. S. lacustris 



32. Diameter vegetative cells 43-50/1, 



median spore wall brown y. S. variforniis 



32. Diameter vegetative cells 48-60 ju, 

 median spore wall [ ? ] "bluish- 

 green" 36. 'S'. sahnii 



ONE CHROMATOPHORE 

 SPORES POLYMORPHIC, MEDIAN WALL SMOOTH 



33. Vegetative cell diameter 17-21 11, chro- 



matophore 1-2, spores variable 22. 5. pratensis 



33. Vegetative cell diameter 22-40 m, chromatophore i 34 



34. Diameter vegetative cells 27-40 /a, 



spores variable in form 37- '^- lutetiana 



34. Diameter vegetative cells 22-30 /x, 



spores variable in form 39- '^- polymorpha 



ONE CHROMATOPHORE 

 SPORES WITH MEDIAN WALL NOT SMOOTH 



35. Spores ellipsoid 37 



35. Spores ovoid 36 



35. Spores globose 270. S. czurdae 



36. Median spore wall scrobiculate. . 42. S.luteospora 

 36. Median spore wall reticulate. ... 43. S. sulcata 

 36. Median spore wall finely wrin- 

 kled 44. iS. westii 



36. Median spore wall punctate 45- '^- obovata 



36. Median spore wall granulate. ... 46. S.asiatica 



36. Median spore wall of 2 layers. . . 263. S.che\iangensis 



37. Vegetative cells usually less than 33 /a in diameter 38 



37. Vegetative cells 33-45 M in diameter 42 



37. Vegetative cells more than 45 /x in diameter 45 



38. Fertile cells cyHndric or enlarged 39 



38. Fertile cells inflated on both sides 40 



38. Fertile cells inflated on the inner side 41 



