THE GEOLOGICAL HISTORY OF PLANTS. 



with Archceopteris is that which I haye named Platyphyl- 

 lum, and which grew on a creeping stem or parasitically 

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



Fig. 24. — Archceopteris Jachoni, Dawson (Maine). An Upper Erian 

 fern, a, 6, Pinnules showing venation. 



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

 Canada," 1871, &c. 



