\ 111 INTRODUCTION. 



2. Variolariae. Stem shield bearing, or warty ; shields leaf-bearing, sur- 

 rounding the stem spirally. 



3. Calamitae. Stem striated, intercepted with sutures at the articulations. 



4. Sgringodendron. Stem arborescent, in the form of pipes agglutinated 

 together, with naked glandules surrounding the stem spirally. 



In the second number he adds to these the following genera : 



5. Rhytidolepis. Stem arborescent, streaked longitudinally with elevated 

 wrinkles ; shields surrounding the stem spirally. 



6. Flabellaria. Leaves part stalked, divided and expanded like a fan. 



7. Schlotheimia. Stem jointed, contracted at the articulation, verticillate. 



8. Annularia. Leaves disposed in a whirl, inserted in a proper ring. 



9. Noeggerathia. Stem as thick as a goose-quill; leaves alternate, approxi- 

 mate, reverse-ovate, half embracing the stem, pectinato-toothed at the 

 top, the remainder of the edge uncut. 



10. Osmunda. 



1 1 . Asplenium. 



The Count does not give any .character to these genera, but refers them to 

 the recent forms. 



12. Rotularia. Leaves verticillate, expanded in the form of a small wheel. 



The third number of Count Sternberg's work contains the following increase 

 of his genera : 



13. Lepidolepis. Scale-like cicatrices truncated at their top. 



14. Thuites, of which he gives no characters but refers to his figures. 



15. Antholiles. 



16. Carpolites. 



17. Conites. Fossil strobili. 



18. Sphenoptcris. 



19. Polypodiolithus. 



20. Mj/riophi/lliles. 



21. Phjlliles. 



22. Algacites, which the French translator, on obtaining the opinion of Prof. 



Agardh, has changed into Sargassum; that celebrated algologist having 

 considered it as identically the same as that genus of recent algae. 



