ee Fifth Supplement to the A. O. U. Chech-List. 59 
to hear next fall from such as are willing to study the shells left 
in and about deserted nests, and to watch the process wherever 
they have the opportunity; also the time required for the down 
to burst forth from the enclosing sheath or envelope. I have 
known this to cause a difference of opinion as to whether the 
young of a certain bird were dark slate-color or pure white, when 
it was only a matter of the difference of some hours or days in 
their age. The skin and cylindrical hairs were dark in this 
case, but the down was white. Each was looking at the other 
side of the traditional shield. 
[Plate II represents the Black Duck Group in the American Museum of 
Natural History, New York City. The nest, young birds, and accom- 
panying accessories were collected by Mr. Jenness Richardson, on Gard- 
ener’s Island, New York, May 9, 1889, by whom also the group was 
mounted at the Museum. This group is No. 46 of the Museum series of 
bird groups prepared by Mr. Richardson. —Ep.] 
FIFTH SUPPLEMENT TO THE AMERICAN ORNITH- 
OLOGISTS’ UNION .CHECK-LIST OF 
NORTH AMERICAN BIRDS. - 
By orpER of the Council of the American Ornithologists’ 
Union the Committee on Classification and Nomenclature of 
North American Birds has prepared the following report on the 
species, subspecies, and changes of nomenclature proposed 
during the year ending November, 1892, forming the Fifth Sup- 
plement to the American Ornithologists’ Union Check-List. The 
Committee met in Washington, Nov. 1S-19, 1892, with the fol- 
lowing members present: Allen, Chapman, Coues, Merriam, and 
Ridgway. 
The numbers at the left of the scientific names facilitate colla- 
tion with the Check-List. The interpolated species and sub- 
species are numbered in accordance with the provision made 
