

LIST OF ILLUSTRATIONS 



Portrait of the Author (1916) .... Frontispiece 



FIG. PAGE 



1. Psilophyton. [Dawson (1859)] 15 



2. Psilophyton. [Reid and Macnair (1896)] .... 16 



3. Psilophylon princeps, Dawson. [Dawson (1871)] ... 17 



4. Psilophyton princeps, Dawson. [Halle (1916)] ... 18 



5. Psilophyton princeps, Dawson. [Dawson (1859)] ... 19 



6. Psilophyton princeps, Dawson. [Halle (1916)] ... 21 



7. The emergences of Psilophyton and Rhynia. [Kidston and Lang 



(1917) and Halle (1916)] 25 



8. Arthrostigma gracile, Dawson. [Kidston (1893)] ... 27 



9. Arthrostigma gracile, Dawson. [Halle (1916)] ... 27 



10. Thursophyton Milleri, (Salt.). [Nathorst (1915)] ... 28 



11. Thursophyton Milleri, (Salt.). [Reid and Macnair (1899)] and 



T. hostimense, (P. & B.). [Potonie and Bernard (1904)] . 30 



12. Ptilophyton Thomsoni, Daws. [Salter (1859)] ... 31 



13. Ptilophyton Thomsoni, Daws. [Carruthers (1873)] ... 32 



14. Ptilophyton (?) hostimense, (P. & B.). [Stur (1881)] . . 33 



15. PseudosporochnusKrejc'ii,(StUT). [Potonie and Bernard (1904)] 33 



16. Pseudosporochnus Krejcii, (Stur). [Potonie and Bernard (1904)] 34 



17. Broggeria norvegica, Nath. [Nathorst (1915)] . . . 35 



18. Barrandeina Dusliana, (Kr.). [Potonie and Bernard (1904)] . 36 



19. Barinophyton Richardsoni, (Daws.). [White (1905)] . . 38 



20. Parka decipiens, Flem. [Don and Hickling (1917)] . . 39 



21. Lithophyllum lichenoides, (E. & S.) and Melobesia membranacea 



(Esper) Lamour. [Rabenhorst, Kryptogamen-Flora (1885)] 40 



22. Zosterophyllummyretonianum,Penh. [Reid and Macnair (1899)] 41 



23. Hostimella hostimensis, P. & B. [Potonie and Bernard (1904)] . 43 



24. Sphenophyllum subtenerrimum, Nath. [Nathorst (1902)] . . 52 



25. Hyenia sphenophylloides, Nath. [Nathorst (1915)] ... 53 



26. Pseudobornia ursina, Nath. [Nathorst (1902)] ... 54 



27. PsygmophyllumKolderupi,Nath. [Nathorst (1915)] . . 55 



28. Archaeopteris hibernica, (Forbes). [Carruthers (1872)] . . 56 



29. Archaeopteris Archetypus, Schmalh. [Nathorst (1904)] . . 57 



