£55 Commonwealth Avenue, Boston, Mass. U.B.A. 
Decmber 10th, 1928. 
My Boar Dr. Calderon: 
At the request of .Dr. Paul C. 
Standleyof the United States National Museum, I am 
sending to your address this day several packages 
of books for the botanical library of the Daborat- 
orio Quimieo. Perhaps as an exchange you will be 
able to help me secure orchids of El Salvador for 
my Orchid Herbarium. I have just completed the de¬ 
termination of some of your numbers submitted by 
Dr. Standlay. f ihssa have stimulated a desire to se¬ 
cure more material from your country. Determinations 
will be made promptly and carefully. I should expect 
to find many representatives of Spiranthes in El Sal¬ 
vador. An interesting species of this group was among 
the specimens just identified. 
We know so little aoout the orchids of El Salvador 
that I am most anxious to assemble them. 
'V ' • ‘ ' ... 
& With best wishes for the Ho&idays 
-j, ' Yours truly. 
Dr. Salvador Calderon. 
;/■ ■ CotiiA.- O-v-w 
