INTRODUCTION 



This is the seventeenth in a series of bulletins of the United States 

 National Museum on the life histories of North American birds. 

 Previous numbers have been issued as follows: 



107. Life Histories of North American Diving Birds, August 1, 1919. 



113. Life Histories of North American Gulls and Terns, August 27, 1921. 



121. Life Histories of North American Petrels and Pelicans and Their Allies. 



October 19, 1922. 

 126. Life Histories of North American Wild Fowl (part), May 25, 1923. 

 130. Life Histories of North American Wild Fowl (part), June 27, 1925. 

 135. Life Histories of North American Marsh Birds, March 11, 1927. 

 142. Life Histories of North American Shore Birds (pt. 1), December 31, 1927. 

 146. Life Histories of North American Shore Birds (pt. 2), March 24, 1929. 

 162. Life Histories of North American Gallinaceous Birds, May 25, 1932. 

 167. Life Histories of North American Birds of Prey (pt. 1), May 3, 1937. 

 170. Life Histories of North American Birds of Prey (pt. 2), August 8, 1938. 

 174. Life Histories of North American Woodpeckers, May 23, 1939. 

 176. Life Histories of North American Cuckoos, Goatsuckers, Hummingbirds, 



and Their Allies, July 20, 1940. 

 179. Life Histories of North American Flycatchers, Larks, Swallows, and Their 



Allies, May 8, 1942. 

 191. Life Histories of North American Jays, Crows, and Titmice, January 27. 



1947. 

 195. Life Histories of North American Nuthatches, Wrens, Thrashers, and Their 



Allies. July 7, 1948. 



The same general plan has been followed, as explained in previous 

 bulletins, and the same sources of information have been utilized. 

 The nomenclature of the 1931 Check-list of the American Ornitholo- 

 gists' Union has been followed. 



An attempt has been made to give as full a life history as possible 

 of the best-known subspecies of each species and to avoid duplication 

 by writing briefly of the other subspecies. In many cases certain 

 habits, probably common to the species as a whole, have been recorded 

 for only one subspecies; as such habits are mentioned only under the 

 subspecies on which the observations were made, it would be well to 

 read all the accounts in order to get the whole story for the species. 

 The distribution deals with the species as a whole, with only rough 

 outlines of the ranges of the subspecies, which in many cases cannot 

 be accurately defined. 



The egg dates are the condensed results of a mass of records taken 

 from the data in a large number of the best egg collections, as well as 



VI 



