64 OUR NATIVE FERNS AND THEIR ALLIES. 



seem to connect the club-mosses with the Cycads. Restora- 

 tions of Lepidodendron may be seen on the left-hand side of the 

 frontispiece, and of Sigtllaria on the right. Isoetes dates back 

 to the Miocene (Tertiary) and Marszlza and Pilularia to the 

 same period. 



