89 
Garden every facility was given me for the prosecution of the 
work. JI am indebted to the latter institution for the use of a 
chemical laboratory which was placed at my disposal and fora 
plentiful supply of material of all kinds as well as for encourage- 
ment and helpful suggestions from the members of the staff. 
In view of the fact that I have received letters making claims 
in connection with the results attained above, and als t 
many unauthorized newspaper notices have been published in 
which the facts are incorrectly reported I take occasion to say 
that I have never heard a lecture on “ pop corn” or any other 
subject which suggested the investigation noted above and that 
the principles used in the process were discovered directly in my 
own experiments, being entirely different from the ‘‘ popping ”’ of 
corn or other grains. The above note is the first statement I 
have made for publication upon this subject, and I do not hold 
myself responsible in any degree for the various sensational and 
misleading newspaper reports that have appeared purporting to 
describe the methods used. 
ALEXANDER P. ANDERSON. 
CoLuMBIA UNIVERSITY, May 2, 1902. 
REPORT OF DR. D. T. MACDOUGAL, FIRST 
ASSISTANT, ON AN EXPEDITION TO 
ARIZONA AND SONORA. 
Dr. N. L. Britton, Director-in- Chief. 
Dear Siy: I have the honor to present the following report 
of my operations in Arizona and Sonora in February and March, 
1902. 
Pursuant to your instructions I left New York January 3 Ist, go- 
ing via New Orleans to Tucson. Professor J. W. Toumey, now of 
the Yale School of Forestry, had formed a collection of cactuses, 
agaves and yuccas on the grounds of the University of Arizona 
at this place during his term of service at that institution, and 
a few days’ study of this plantation yielded information which 
gave valuable guidance in securing cacti and other xerophytic 
plants for the newly completed ranges of the conservatories. I 
am indebted to President Adams of the University, and Director 
