PRELIMINARY NOTES. 323 



thereto follows the description of each formation. Not only the gross 

 adaptations, such as can be detected in the field with the unaided 

 eye, but also peculiarities of minute structure which are to be 

 regarded as fitting the plant to its surroundings, arc here considered. 



A more detailed description of the leaf anatomy of a number of the 

 abundant or otherwise interesting species is presented in a succeed- 

 ing chapter. Mere the species are arranged in their systematic order, 

 for convenience of reference. The anatomical descriptions are very 

 far from being complete. In most cases merely the leaf is considered, 

 and only those of its characters are mentioned which are believed 

 to be directly related to the environment. A discussion of the broad 

 geographical relationships of the flora of the Dismal Swamp region 

 and a list of all species collected or noted complete the purely scientific 

 portion. 



As an indispensable preface to both the economic and the scientific 

 sections, the first three chapters are devoted to the climate of the 

 region, its geography and physiography, and its geology. Statistics 

 of climate were obligingly communicated by the Chief of the United 

 States Weather Bureau. Many of the data contained in the second 

 chapter, and practically the whole of the third, were taken from man- 

 uscript of the text to the Norfolk folio of the Geological Atlas of the 

 United States, to which access was had by the courtesy of the author, 

 Mr. N. II. Darton, of the United States Geological Survey. 



.V list of all literature consulted in the preparation of the report is 

 appended. 



Of the photographs here reproduced, a considerable number were 

 taken by the author. Others were made by Mr. Frederick V. Coville. 

 A number of Dismal Swamp views were obtained from Mr. John G. 

 Wallace, of Wallaceton, Va. Finally, an excellent series of photo- 

 graphs belonging to the Geological Society of America, several of 

 which had previously b?en reproduced in Prof. N. S. Shaler's "Gen- 

 eral Account of the Fresh-Water Morasses of the United States," were 

 kindly placed at our disposal by the Director of the United States Geo- 

 logical Survey. Professor Shaler's paper, a valuable contribution to 

 knowledge of the geology, physiography, and vegetation of the region, 

 was freely consulted and is often quoted in this report. 



The author wishes to express his great indebtedness to the special- 

 ists to whom the determination of various groups is credited in the 

 List of Species Collected. Mr. Theodor Holm, of Brookland, D. C, 

 rendered valuable assistance in the preparation of the anatomical 

 notes. Dr. E. L. Greene courteously extended the facilities of his 

 valuable library. To Mr. C. D. Beadle, of the Biltmore Herbarium, 

 Biltmore, NT. G, I am indebted for data as to the northern limit of 

 many Austroriparian plants. For various courtesies and much useful 

 information I wish to express my obligations to the following gentle- 

 men: Mr. T. li. Ballantyne and the late Maj. Charles Pickett, of Nor- 



