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work, the certainty of its results, and the nature of the methods 
by which it is carried on. 
One of the very first things for which the pharmacognosist 
looks in identifying a drug powder or fragment is the presence 
or absence of starch grains, and their peculiarities, if present. 
Starch is probably in most cases the first compound formed by 
the leaves of the plant out of carbon dioxide and water, and most 
plants store it in the form of granules. These granules have a 
distinct plan of structure, which differs in different plants. The 
size and form are also characteristic of the plant producing 
them. I exhibit here a very instructive illustration of a group of 
starch grains, taken from Kraemer’s work. Observe the very 
large grains of potato and arrow-root, with their very distinct 
rings. The hilum is near the end in both, but in the second it is 
fissured. Wheat starch has a rather small grain, distinguished by 
its lenticular shape, very well seen in the granules which present 
their edges to view, and by the central hilum. Corn starch is 
peculiar in its angular outline and its fissured central hilum. 
Curcuma starch is very beautifully formed and marked, although 
it reminds one of the appearance of some bugs. All starch 
grains must be measured, the upper limits of size being fairly 
constant. Their occurrence singly or in groups is also signifi- 
cant of their identity. In this picture of Colchicum corm you 
see them mostly grouped in threes and fours, and having a very 
peculiar hilum. 
This next picture illustrates potato starch grains altered by 
moist heat. Itis not unusual fora dishonest drug miller to grind 
up with a good drug a portion of exhausted material, from which 
medicine has already been made. Such material is first put into 
a still to drive off its alcohol, in which process it is steamed. 
this steaming it is swollen and its shape altered and it loses its 
characteristic markings. 
n this specimen of /z#/a, or Elecampane, you look in vain for 
starch-grains. It belongs to that largest of all plant families, the 
daisy family, which forms none. This family yields a great 
number of drugs and you at once see that if adulterated with a 
drug from another plant, we are very likely indeed to find starch 
