MOUGEOTIA 87 



52. Zygosporangia regularly dividing the gametangia 53 



52. Only some of the zygosporangia 



dividing the gametangia 5. M. calcarea 



53. Diameter vegetative cells 3-5-4-5M 74. M.elegantula 



53. Diameter vegetative cells more than 7^1 54 



54. Diameter vegetative cells 8-9 /a. ... 82. M. virescens 

 54. Diameter vegetative cells 11-14/^.. 86. M.paludosa 

 54. Diameter vegetative cells 9-1 1 /a... 96. M.subpalndosa 



55. Vegetative cells 3-5 i^ in diameter 73- ^- delicata 



55. Vegetative cells 6-8^1 in diameter 77. M. viridis 



56. Zygospore angles with rounded processes 37 



56. Zygospore angles retuse or truncate 58 



57. Spores regularly quadrate, processes 



short 66. M. corniculata 



57. Spores irregularly quadrate, processes 



long 68. M. uberosperma 



58. Spores with processes truncate.... 65. M.americana 

 58. Spores with processes retuse 69. M. craterophora 



59. Zygospores concave-cylindric 44. M. varians 



59. Zygospores quadrate, quadrate-ovoid to globose 60 



60. Dimensions of spores less than 30 ju, 88. M.jragilis 

 60. Dimensions of spores greater than 



35/A 71. M. granulosa 



60. Dimensions of spores greater than 



50 ju. 72. M. capucina 



61. Spores concave-quadrate, wall minutely 



verrucosa 76. M. gracillima 



61. Spores quadrate, sides straight, concave or convex, wall mi- 

 nutely to coarsely punctate 62 



62. Diameter vegetative cells usually less than 13 m 63 



62, Diameter vegetative cells usually more than 13 /a 68 



63. Vegetative cell diameter usually less than 8 /a 64 



63. Vegetative cell diameter 8-13 /a 67 



64. Diameter vegetative cells 4-5 z^, re- 

 produces mostly by aplanospores . . 75. M.boodlei 

 64. Diameter vegetative cells 5-8 (-9) /a 65 



65. Zygospores with angles rounded, bulg- 

 ing into the gametangia 81. M. austriaca 



65. Zygospores with angles produced (£ 



65. Zygospores with angles retuse, not 



produced 80. M. tumidula 



