SPIROGYRA 135 



END WALLS PLANE 

 (one-) two to sixteen CHROMATOPHORES 



46. Spores globose, ovoid, or ellipsoid, not laterally com- 

 pressed 47 



46. Spores globose, ovoid, or ellipsoid, laterally compressed 105 



47. Median spore wall smooth 48 



47. Median spore wall not smooth 75 



SPORES NOT LATERALLY COMPRESSED 

 MEDIAN WALL SMOOTH 



48. Vegetative cells with less than 9 chromatophores 49 



48. Vegetative cells with more than 9 chromatophores. ... 71 



49. Fertile cells cylindric, or enlarged 50 



49. Fertile cells inflated 72 



50. Spores ellipsoid or cylindric-ellipsoid 51 



50. Spores ovoid or cylindric-ovoid, rarely globose 62 



51. Vegetative cells usually less than 45 /a in diameter 52 



51. Vegetative cells usually 45-60 /a in diameter 54 



51. Vegetative cells more than 60 /la in diameter 56 



52. Chromatophores 2 to 3 in each cell 53 



52. Chromatophores 2 to 4, diam- 

 eter vegetative cells 32-37 ju- 66. S. irregularis 



52. Chromatophores 3 in each cell. . 67. S.juellebornei 

 52, Chromatophores 2 in each cell, 



spores 2^7,2 iJi X 51-61 ju, 68. 5. microspora 



52. Chromatophores 2 in each cell, 



spores 38-42 /x X 60-78 /x 69. 5, hollandiae 



53. Diameter vegetative cells 21-32 ^u, 70. S.submarina 



53. Diameter vegetative cells 36-41 /a 71. 5. rivularis 



53. Diameter vegetative cells 38-48 fi 72. 5. biformis 



54. Chromatophores, 3, 1-3, or 2-3 55 



54. Chromatophores 2-4 li- ^- hyalina 



55. Chromatophores 3, diameter vegeta- 

 tive cells 55-60 )U, 74- '^- pseudoneglecta 



55. Chromatophores (i-)3, diameter veg- 

 etative cells 48-54 i". IS- ^- Columbiana 



55. Chromatophores 2 to 3, diameter veg- 

 etative cells 49-62 M 76. 5. angolensis 



56. Diameter vegetative cells between 60 and 80 /a 57 



56. Diameter vegetative cells between 80 and 120 ix 60 



56. Diameter vegetative cells more than i20ju. 61 



