Names of 
Dust Plants 
16 
HOUSEHOLD BACTERIOLOGY. 
All of these dust-plants have to be studied under' 
the microscope and are therefore called micro-organ¬ 
isms . Microbe —a name given by Louis Pasteur— 
which from its derivation would include all, has 
come gradually to be applied to one class, the bac¬ 
teria. Still a third word, germ, which really means 
the beginning, or that first living cell which produces 
a more complex form, is becoming restricted to the 
micro-organisms that cause disease, as the germ of 
tuberculosis, the germ of typhoid fever, etc. All 
~ these names may apply to micro- 
w scopic animal forms as well.- . Strict¬ 
er w jy speakings a p dust-plants are germs, 
all are microbes, all are micro-organ¬ 
isms. 
The “garden” will show two 
kinds of plants and sometimes a 
third, although this is not so com¬ 
mon in house dust. We will now 
see what these three kinds of plants 
are, two of which we may expect 
to find in all houses at anv time. 
Fig. 7. Typical 
Forms of Bacteria. 
(a) Cocci, or Ball 
Forms. (hj Bacini, Ti le third, wild yeast, would very 
or Rod-shaped ’ J * J 
Forms, or 4 likely be caught if we planted our 
Forms - dust garden under the apple trees in 
summer time. 
BACTERIA 
Let us find out first what the plants are like which 
make the smooth, glossy, shiny colonies, whether round 
or radiate. These are the bacteria, and each colony 
