PLATE XLI. 



PAGE 



Figs. 1, 2. Selaginella marylandica Fontaine 307 



1. Specimen from Vinegar Hill, Maryland (after Fontaine). 



2. Part of same. X 3. 



Figs. 3-6. Equisetum Burchakdti (Dunker) Brongniart 310 



3. Rhizome with tubers, New Reservoir, D. C. (after Fontaine). 



4. Branching specimen, Dutch Gap, Virgina (after Fontaine). 



5. 6. Diagrammatical sketch of sheaths of same (after Fontaine). 



Figs. 7, 8. Equisetum Lyelli Mantell 311 



7. Specimen from Fredericksburg, Virginia (after Fontaine). 



8. Same showing sheath (after Fontaine). 



540 



