58 West & West . — Observations on the Conjugatae . 
Fig. 69. Spirogyra condensate/, (Vauch.), Kutz. x 250. 
Figs. 70, 71. Hybrids from Mitcham Common, Surrey, x 250. Conjugation 
between two species of Spirogyra of different thickness. 
Fig. 72. Spirogyra inflata (Vauch.), Rabenh. x 100. 
Fig. 73. Spirogyra Jurgentii, Rabenh. x 100. 
Figs. 74, 75. Spirogyra bellis (Hass.), Crouan. x 140. 
Fig. 76. Spirogyra velata , Nordst. x 220. 
Figs. 77, 78. Spirogyra bellis (Hass.), Crouan. x 140. 
Figs. 79, 80. Spirogyra velata, Nordst. x 220. 
Fig. 81. Spirogyra gracilis (Hass.), Kutz. forma, x 350. 
Fig. 82. Spirogyra varians (Hass.), Kutz. x 520. Aplanospore. 
Fig. 83. Zygnema leiospermum , De Bary. x 520. Showing aplanospore. 
Figs. 84, 85. Spirogyra velata , Nordst. Two zygospores germinating imme- 
diately after formation. x 220. 
