CONCLUSIONS. 
OO 
WE may sum up as follows the actual state of our 
knowledge upon the bacteria : — 
1. The bacteria are cellular organisms of vege- 
table nature. 
2. Their organism is more complicated . than 
was for a long time believed. The _ principal 
points brought to light are: their structure, the 
presence of cilia, the nature of the substances 
contained in their protoplasm, — colored granules, 
grains of sulphur, ete. 
3. The forms of torula, zooglea, leptothrix, my- 
coderma, ete. 
4. The multiple affinities of the bacteria, on the 
one hand with the alg, on the other with the 
fungi, differently understood by authors, and their 
development, still unknown for the greater num- 
ber of species, make it impossible to classify these 
beings except in a provisional manner. | 
5. This development, well studied in several 
species of Bacillus, has proved that bacteria may 
multiply not only by fission, but also by formation 
of spores, and even by veritable sporangia. 
6. These spores or permanent germs are the 
