42 SCANDINAVIANS AND 
Some Rocky Mountain Chrysothamni, 1900. 
Cryptogams of Wyoming, 1900. 
Contributions from the Rocky Mountain Herbarium, I—VII, 1900—’06. 
Broom-grasses of Wyoming, 1901. 
An Analytical Key to Some of the Common Plants of the Rocky Mountain 
Region, 1902. 
The Genus Hedysarum in the Rocky Mountains, 1902. 
Native Vines in Wyoming Homes, 1902. 
Psilostrophe, a Neglected Genus of Southwestern Plants, 1903. 
The Wheat-grasses of Wyoming 1903. 
Plantz Andrewsianez, 1904. 
New Plants from Nevada, I—II, 1904—’05 
Plant#e montrosenses, I [together with Kennedy], 1906. 
Per Axel Rydberg was born the 6th of July, 1860, in Ohd Par- 
ish, Westergétland, Sweden, and studied at the Royal Gymnasium 
at Skara, where he was graduated in 1881. The following year, 
he emigrated to America. From 1884—1893 he taught at Luther 
Academy, Wahoo, Neb. He received his M. A. degree at the Uni- 
versity of Nebraska in 1895 and his Ph. D. at Columbia Univer- 
sity, New York, in 1898; was professor of natural sciences and 
mathematics at Upsala College, Kennilworth, N. J., 1895—6 and 
1897—9, and issince that time one of the curators of the New York 
Botanical Garden. In the summers of 1891—93, 1895, and 1896 
he was a field agent of the United States Department of Agricul- 
ture and collected in western Nebraska, the Black Hills of South 
Dakota, Montana, Idaho, Wyoming and Colorado. In 1897, 
1900, and 1905 he collected for the New York Botanical Garden 
in Montana, Colorado, California, and Utah. The list of his pub- 
lications is omitted for obvious reasons. 
List of Papers Published by Dr. P. A. Rydberg.* 
On the American Black Cottonwood, 1893. 
Flora of Nebraska. Part 21, Rosales, 1895. 
New species of Physalis, 1895. 
Flora of the Sandhills of Nebraska, 1895. 
Flora of the Black Hills of South Dakota, 1896. 
The North American species of Physalis and related genera, 1896. 
Notes on Potentilleae., I-VI, 1896—7 
Notes on two western plants, 1897. 
Antennaria dioica and its North American allies, 1897. 
Rarities from Montana, 1897. 
_* Editor's Note. This paper would be lacking in a most important particular, if the writ- 
ings of its author were omitted. The editor, for that reason, takes the liberty to here insert a8 
compl te al he hast ble to fthe published papers of Dr. P. A. Rydberg to 
_ the present date. J 
