Introduction 



have been pleasantly and profitably associated at various times, on 

 expeditions over the Peninsula. 



From Professor M. L. Fernald I have received many specimens 

 from the Coastal Plain of Virginia, including a number collected in 

 the portion of that state which is included in the Peninsula. Ernest 

 J. Palmer, of the Arnold Arboretum, has helped with the critical 

 genus Crataegus. To Professors C. 0. Houghton and F, C. Hough- 

 ton, of the University of Delaware, and to Mr. H. Raymond 

 Baker, of the State Board of Agriculture at Dover, I am indebted 

 for valuable information as to localities for many Delaware species 

 of plants. 



It is a pleasure to acknowledge my especial indebtedness to my 

 friend Dr. Frank Morton Jones, biologist, of Wilmington. Dr. 

 Jones has been a constant collaborator in the present project, and 

 my companion on most of the longer journeys through the Peninsula 

 and many of the shorter ones. His inspiration and wise guidance 

 have been an important factor in initiating the undertaking, and 

 carrying it through to completion. 



To my wife, and to my brother, S. A. Tatnall, I am indebted 

 for helpful criticism of the text of the Introduction. 



Symbols and Abbreviations Used in the Text 



Counties. It is somewhat inconvenient for the present purpose 

 that two counties on the Peninsula, in Delaware and Maryland, 

 respectively, have been given the same name — Kent. They are 

 contiguous for about three miles. However, the code which 

 follows, and which is used throughout, will readily distinguish 

 between them. 



Delaware Maryland 



NC = New Castle Ce = Cecil 



K = Kent Ke = Kent 



S = Sussex QA = Queen Anne's 



Ca = Caroline 

 Ta = Talbot 

 Virginia Do = Dorchester 



Ac = Accomac Wi = Wicomico 



No = Northampton Wo = Worcester 



So = Somerset 



xxiii 



