Plate XX ; Figures 122 to 133; Magnified iooo Diameters. 



Fig. 122. Staurastrum dejectum var. conver- 



gens Wolle ..... page 62 



Figs. 123,124. Staurastrum orbkulare (Ehrb.) 



Rail's " 



Fig. 125. Staurastrum dejectum var. mucro- 



natum Ralfs .... " 



Figs. 126. 127. Staurastrum iiiegacaiithuni Lund. 



Fig. 128. Staurastrum brevispinuhi Breb. 



Fig. 129. muricatum Breb. 



Fig. 130. erasum Breb. . . " 



Fig. 131. " ' Show- 



ing multiplication by division 



Fig. 132. Staurastrum odondtum Wolle . 



Fig. 133. hirsutum (Ehrb.) Breb. " " 



