-scnbe only the ferns, leaving the other orders for a future 

 period; when the author, in connexion with his friends, the 

 Rev. L. D. Schweinitz, and A. Halsey, Esq. proposes to 

 give a Cryptogamic Flora of the United States. Large col- 

 lections have already been made towards this work. 



The names of genera and species proposed by the author 

 have an asterisk (*) annexed to them. To a few doubtful 

 plants the mark (+) is added. It is probable that these 

 last should all be expunged from our Flora. 



The detailed descriptions are always original, except in a 

 few cases, where the authority is given. 



The author would not forget his friends who have assisted 

 him in contributions to this work. Although their names ap- 

 pear so frequently on its pages, he must express his particu- 

 lar obligations to the following gentlemen : — Prof. Bigelow, 

 and J. Oakes, Esq. for plants of the vicinity of Boston, the 

 White Hills, &c. ; Prof. C. Dewey, Dr.' J. Porter, Dr. 

 Cooley, and the Rev. Mr. Hitchcock, from various parts of 

 Massachusetts ; Dj. E. Ives, Dr. J. Hooker, and Mr. J. B. 

 Brace, from Connecticut; Dr. L. C. Beck, Mr. J.Tracy, 

 and Dr. E. James, from Albany and its neighbourhood ; Dr. 

 M. Stevenson, from the northern parts of the State of New- 

 York ; Dr. J. Barratt, from the Highlands; VVm. Cooper, 

 and A. Halsey, Esqrs. from the vicinity of this city and else- 

 where ; and Capt. Le Conte, Mr. A. Eaton, and the Rev. 

 Mr. Schweinitz, from various parts of the northern and 

 middle States. To the Messrs. Prince, of Flushing, he is 

 indebted for unrestrained access to the Linna^an Botanic 

 Garden ; which extensive collection embraces a large pro- 

 portion of the plants of our country, capable of cultivation. 

 Their establishment merits the extensive patronage it re- 

 ceives. 



As this work, from its size, may be inconvenient for rc« 

 ference in the field, or may be too expensive for many bo- 

 tanists, a Compendium, comprising the essential generic and 

 specific characters of all the plants described in the larger 

 Fiora, has been prepared, and will shortly be published. 



Should the present undertaking be favourably received by 

 the botanic world, it is the intention of the author to publish 

 a General Flora of North-America, to include all the dis- 

 coveries made since the work of Mr. Pursh, now amounting 

 to many hundred species. Collections are continually making 

 for this purpose, and the aid of botanists in all parts of our 

 country, by the communication of local catalogues, observa- 

 tions, and dried specimens, is respectfully solicited. 



N£v)'York, July ^Oth, \B1A. 



