BY JOHN THOMSON, M.B. 19 
sometimes at one end, but they are always constant for the 
same species. 
There is rarely more than one spore in a bacillus, and each 
spore, under favourable conditions, produces only one parent 
form. 
Muir and Ritchie say “ 
as a resting place of a bacterum, and is rarely, if ever, to be 
considered as a method of multiplication.” 
sporulation is to be looked upon 
Il.—Arthrospores are spores formed by joints, and about 
the existence of these there seems to be a considerable element 
of uncertainty. 
Classification according to (4) virulence and (7) colour 
may be grouped, together with the conditions the 
Bacteria give rise to, or the changes they effect, in the media 
in which they grow. 
I_—Zymogenic— 
Ferment producing 
I1.—Pathogenic— 
Disease producing 
III.—Saprogenic— 
Putrifaction producing 
IV.—Chromogenic— 
Colour producing 
V.—Photogenic— 
Light—phosphorescence—producing. 
Some micro-organisms are flagellated, that is. they have 
long, slender, lash-hke appendages ; and the motility which 
some of these organs enjoy is supposed to be due to their 
flagella. 
When there is but one flagellum, the organism is said to 
be monotrichic ; when the flagella surround the organism, 
it is called peritrichic, and when the flagella are tufted or in 
clumps, the term lophtrichic is used. 
Many organisms are encapsuled—surroundeds by a 
homogeneous covering or capsule. 
The rate of Multiplication among Bacteria—The numbers 
in all the classes of bacterial varieties are “as the sand 
which is by the sea shore, innumerable,” and it is almost 
impossible to realise their rapidity of multiplication. 
