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in a large number of varieties. Several hundred varieties 
of rice, chiefly from the Philippines, will be found of 
special interest. Of Indian corn, we show not only the 
highest product of modern plant breeding, but many 
primitive forms, not far removed from the original wild 
product. Dhoura or Kaffir corn is another highly im- 
portant grain, little known among us except as a chicken 
food, but constituting the staple article of diet of millions 
of oriental people. Of the more common grains, such as 
wheat, oats, and barley, the products of different countries 
have been gathered, as well as sets representing the com- 
mercial grading by the New York Produce Exchange. 
Drugs. Cases 115-174. Our materia medica collec- 
tion is the largest in the Museum, with the possible ex- 
ception of that of foods. It includes only the crude, 
ground, and powdered vegetable drugs, with a few con- 
stituents extracted from them. It has not been deemed 
advisable to include manufactured medicinal prepara- 
tions, partly because of their great number, and partly 
because of their liability to deterioration when kept for 
long periods. It is not to be understood that the presence 
of a drug in this Museum is an endorsement, or even an 
indication of its value. It is recognized that a large 
minority, if not an actual majority of vegetable drugs that 
are or have been used, are either worthless or of so little 
value as not to be entitled to use. It sometimes happens, 
however, that new discoveries are made regarding the value 
of a drug previously regarded as worthless that reveals it as 
the possessor of important properties. It appears desirable 
also that such a collection should possess historical value, 
which is subserved by including in it all plants that have 
been considerably employed in medicine, without regard 
to the justification for such use. 
The classification of these collections is of similar charac- 
ter to that of the foods. They are first grouped as under- 
ground portions, barks, woods, leaves, flowers, herbs, and 
twigs, fruits, seeds, and miscellaneous parts and products. 
