Pk EE exe, 
T the Sixth Congress of the American Ornithologists’ Union, 
held in Washington, D. C., November 13-15, 1888, it was 
decided to publish a Supplement to the Union's Check-List of 
North American Birds, consisting of the tenable species and 
subspecies, genera and subgenera, added since the publication 
of the Check-List, together with the necessary eliminations and 
the valid changes in nomenclature made since the Check-List 
was issued. The work of revising the proposed additions and 
changes was referred to the Committee on Publications, with 
instructions to publish the results of their work at the earliest 
practicable date, as a Supplement to the Check-List. 
The Committee held a six days’ session immediately after the 
adjournment of the Union, the full Committee being present 
and participating in the work. The Supplement here pre- 
sented records the ruling of the Committee on about one 
hundred distinct questions, involving additions to the Check- 
List or changes in its nomenclature. Besides this, the Commit- 
tee considered some twenty or thirty additional cases of similar 
character, in which the proposed changes were found untenable, 
or in which the material examined was not sufficient to deter- 
mine the question of their validity; and its decision thereon 
may be thus considered as in the main negatively recorded in 
the following pages. All questions of this nature known to the 
Committee at the time of its meeting were acted upon. 
