74 THE GEOLOGICAL HISTORY OF PLAXTS. 



with ArcJuBOpteris is that which I have named Platyphyl- 

 lum, and which grew on a creeping stem or parasiticaHy 

 on stems of other plants, and had marginal fructification.* 



FIG. 24. Archceopteris Jaclcaoni, Dawson (Maine). An Upper Erian 

 fern, a, i, Pinnules showing venation. 



* " Reports on Fossil Plants of the Devonian and Upper Silurian of 

 Canada," 1871, &c. 



