PREFACE XV 



well-established genus. It had come to pass that some 

 plants had from ten to twenty different names, and again 

 several plants had the same name. 



It was decided in 1892, at the Botanical Club of the 

 American Association for the Advancement of Science in 

 Rochester, N, Y., to adopt the code of nomenclature devised 

 by the Paris Botanical Congress and return to the oldest 

 established name for each plant. 



The botanical manuals of Gray and Wood naturally 

 contained many names which did not comply with this 

 regulation. It was not until the "Illustrated Flora of the 

 Northern States and Canada," by Britton and Brown, was 

 published in 1896 that the painstaking task was accom- 

 plished of revising the names of the 4,000 plants included 

 in this flora. Some of the orchids are among those whose 

 scientific names sound unfamiliar. But the orchid lovers 

 who are disturbed by this change from what they learned at 

 school ten or more years ago may rest assured that the 

 nomenclature of botany is now as firmly established as that 

 of zoology. 



The area covered by these illustrations of Mr. Gibson 

 extends from the Atlantic Ocean to the load meridian, and 

 includes the whole state of Kansas, and northward from the 

 parallel of the southern boundary of Virginia and Kentucky 

 to the northern limits of Labrador and Manitoba. 



Thanks are due to Doctor Britton and his associates who 

 materially aided the completion of Mr. Gibson's work by 

 placing all the material of the New York Botanical Garden at 



