304 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
European botanists so commonly treat groups of American plants. 
The genus Allionia, for instance, is made a mere section of Mirabilis, 
and other adjustments of the same kind are made which. although 
they may be the easiest way of disposing of genera, are certainly not 
conducive to clearness. 
In 1902 Mr. M. E. Jones published in his Contributions to West- 
ern Botany“ a paper dealing with the family as it is represented in 
the Great Plateau region, an area in which are found almost all the 
species at that time known to occur in the United States. In the 
same year there appeared in the Bulletin of the Torrey Botanical 
Club? a paper by Dr. Per Axel Rydberg dealing with the Allioniaceae 
of the Rocky Mountains and containing descriptions of a number of 
new species, which is undoubtedly the most critical and valuable 
publication dealing with any group of the American representatives 
of the family. 
The work, the results of which are here discussed, was carried on 
at the New Mexico Agricultural College during the years 1907 and 
1908. The writer had the privilege of examining all the material 
of the Allioniaceae to be found in the herbaria of the following insti- 
tutions and individuals: National Herbarium; Missouri Botanical 
Garden, including the Engelmann and Bernhardi herbaria: Field 
Museum of Natural History; University of California, including 
the Brandegee Herbarium; University of Wyoming; University of 
Nevada; University of Arizona; Mr. A. A. Heller, Mr. K. K. Mac- 
kenzie, Prof. E. O. Wooton, and the New Mexico Agricultural Col- 
lege. He wishes here to express his obligations to the curators or 
owners of these collections; also to Mr. G. E. Osterhout, who furnished 
material for examination. It was only through the kindness of those 
who have charge of these various collections that this work was made 
possible. The author is under special obligations to Prof. E. O. 
Wooton, under whose direction the work was begun and completed, 
The present paper is intended to cover all the representatives of 
the family occurring within the United States and most of those 
found in Mexico and the West Indies, with the exception of the genus 
Pisonia. 
The drawings are by the author, with the exception of Plates 
AXNIV and XXXV, which are by the German artist, W. Liepoldt. 
The author wishes especially to express his indebtedness to Dr. Anton 
Heimerl, who forwarded to him the two latter drawings and the 
descriptions which accompany them, with permission to use them 
here. Doctor Heimerl’s notes attached to the sheets of the National 
Herbarium have also in several instances been of great help in the 
preparation of this paper. 
“#10; 34-54. 629: GSO-GO3. 
