INTRODUCTION 



Fifteen years have passed since Memoir III of the Nuttall Ornithological 

 Club, "The Birds of Essex County, Massachusetts," was published. In these 

 fifteen years many changes have taken place in the bird-life of the County, many 

 more observers have studied it, and many notes have been accumulated. It is the 

 purpose of this Supplement to bring our knowledge of the birds of the County 

 up to date, and in order that it may be complete in itself all the species are listed 

 whether or not there are any changes or additions in the annotations. 



Changes are made in the nomenclature wherever necessary to conform to the 

 latest American Ornithologists' Union Check-list.^ As several species new to the 

 list have been added, the serial numbers are changed. The additions are denoted 

 by an asterisk (*). 



In the original Memoir I gave in detail the habits and field-marks of most of 

 the water-birds and of several other birds of especial interest for the County. 

 In this Supplement I have added to the notes on these birds, wherever possible, 

 have increased this list by the addition of the hawks and some others, and in 

 many cases have laid special stress on courtship habits, the study of which in the 

 last fifteen years has especially interested me. 



When the original Memoir was published, there were none living in Essex 

 County sufficiently interested in birds to become members of the American Orni- 

 thologists' Union. At the present time there are twelve members listed from the 

 County. In addition there is a very active club,— the Essex County Ornitholog- 

 ical Club, — with a membership of about fifty having its headquarters and monthly 

 meetings at the Peabody Museum in Salem. The Club was founded in 191 6, but 

 for some eight years prior many of the present members were in the habit of 

 making an annual trip by canoe on the Ipswich River at the height of the warbler 

 migration in May. In preparing this Memoir I have consulted the records of the 

 Club, of which I have the honor to be a charter member. The first number of the 

 annual Bulletin of the Club appeared in December, 1919. 



The number of contributors of notes and records to this Supplement has 

 increased to a great extent. Their names will be found in the Annotated List in 

 connection with their contributions. To all of them I wish to express my 

 grateful thanks. 



Some of the contributors to the original Memoir who have died are : William 



1 The Check-list of 1910 has changed the names of 26 genera and of 16 species of the 

 original list. 



(5) 



