ALTAMAHA GRIT REGION OF GEORGIA 



339 



because the great majority of them are represented in the 

 Carolinas, Virginia, and other regions which had been explored 

 by botanists before his time. Comparatively few new genera 

 in the list have been described since the time of Torrey & Gray, 

 and none of these were based on new species. Michatix de- 



FlG. 22 — Diagram showing dates of description of genera of vascular plants and 

 species of trees and shrubs. 



scribed (and doubtless discovered) more of our genera than any 

 other one author since Linnaeus, 15 being credited to him, 

 most of these being based on single species which he discovered 

 about 15 years before they were published. The following 

 genera included in this work contain only species which have 

 been described since Michaux's time and were presumably dis- 

 covered in the 19th century. 



Elionurus H. & B. 1806. 

 Triplasis Beauv. 18 12. 

 Lophiola Ker 18 13. 

 Elliottia Muhl. 181 7. 

 Baldwinia Nutt. 181 8. 

 Anantherix Nutt. 18 18. 

 Tipularia Nutt. 18 18. 



