CROTONS OF THE UNITED STATES. 
BY A. M. FERGUSON. 
In the prosecution of this study I have been very for- 
tunate in having the material from the larger American 
herbaria, from which to draw the descriptions, namely: 
Missouri Botanical Garden, including the Engelmann col- 
lection, Harvard University, Columbia College, National 
Museum, including the Smithsonian Institution, California 
Academy of Sciences, Iowa Agricultural College and the 
Agricultural and Mechanical College of Texas; and I am 
not unmindful of the favor extended by the gentlemen who 
have charge of these collections. Hurried examinations 
have also been made of the specimens in the herbaria of the 
University of Chicago, Field Columbian Museum, Univer- 
sity of Illinois and the Michigan Agricultural College. 
About a dozen forms have received field study. I wish to 
express further acknowledgments to Dr. J. N. Rose of the 
Smithsonian Institution; for the contributions of notes and 
specimens, to Messrs. J. Reverchon and Wm. Lomas of 
Dallas, Texas, Mr. S. B. Parish of San Bernadino, Cali- 
fornia, Prof. H. Ness of College Station, Texas, and to 
Dr. Charles Mohr of Mobile, Alabama. Lastly, the kindly 
interest of Dr. William Trelease has made the preparation 
of this paper possible. It was through him that the col- 
lections mentioned above were secured, and also the use of 
the excellent facilities for such investigation afforded by 
the Missouri Botanical Garden. For these favors and 
other assistance in the way of suggestion, criticism and 
review, I am very thankful. 
The genus to which the forms here treated belong was 
first named Ricinoides by Tournefort.* Linnaeus, wishing 
* Tournefort, Inst. Herb. 565. pl. 42.3. 1700. 
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