CHLORIS BOREALI-AMERICANA. 



absolutely new to botanists. Two of them, indeed, have been al- 

 ready figured, but without the analyses and details requisite to 

 elucidate their real structure, and settle the questions upon which 

 their ordinal or generic collocation depends. The others, with one 

 exception, belong to genera or species which have not yet been 

 published in any systematic work, at least under their proper 

 names, or which, like the rare Schweinitzia, have hitherto been 

 very imperfectly characterized. Certain plants, which have been 

 first introduced into cultivation at the Botanic Garden under my 

 charge, and which are of special horticultural rather than of strict 

 botanical interest, may also be deemed worthy of occasional illus- 

 tration. Of this kind is the Gaillardia, represented in Tab. IV. 



It will be noticed that the plant which forms the subject of the 

 first illustration is given under a name different from that which, if 

 my conclusions are correctly drawn, it must hereafter bear. This 

 is explained by the fact, that the plate was engraved and the im- 

 pressions taken long before I was able to make the comparisons 

 which rendered the change of name inevitable. 



