1887 .] 
Dr A. B. Griffiths on Micro-Organisms . 
101 
damp place for three weeks. The first micro-organism produces 
an orange colour, and the second a green colour upon bread. These 
micro-organisms grow well in flour-paste at a temperature of about 
34° C., forming a coloured skin upon the surface of the paste. If 
the paste is treated, first of all, with salicylic acid, and then 
M. aurantiacus and B. aeruginosum transplanted to the paste, they 
do not produce any growth, and ultimately die. The salicylic acid 
solution destroys the spores of these two micro-organisms, although 
their spores are said to withstand a temperature of 125° C. 
3. Micrococci found in Diarrhoea. 
The micrococci found largely in secretions from the bowels of 
persons suffering with diarrhoea were transplanted into sterilised 
beef-hroth contained in a Pasteur flask (No. 1), and kept at 40° C. 
They multiplied rapidly during two days. Another flask (No. 2), 
containing sterilised beef-broth and salicylic acid (in the proportion 
of 0’2 grm. of the acid in 1000 c.c. of the broth), was taken and 
inoculated with these actively growing micrococci, but their growth 
was stopped. On inoculating another flask (No. 3) with some of 
the contents of flask (No. 2), and keeping it about 40° C. for three 
weeks, no further growth took place. This proves that the salicylic 
acid had killed the micrococci in question. I am fully aware that 
it has not been thoroughly ascertained whether this micrococcus 
is the cause of diarrhoea, yet, for my purpose, the above is to show 
that the said salicylic acid destroys this micrococcus. 
4. Leptothrix buccalis and Bacillus subtilis. 
These non-pathogenic forms found in the healthy human mouth 
are also destroyed by salicylic acid. When examined under the 
microscope, there was the appearance of the solution of salicylic 
acid perforating the cellulose wall of Bacillus subtilis , and so 
destroying the organism (fig. 3, B). At first we notice the cell- 
wall becomes thinner on the side that the salicylic acid solution is 
being run in between the slide and cover-slip, and is then per- 
forated. 
5. Penicilium glaucum. 
Penicilium glaucum (the mould of preserved fruits, old leather, 
&c.). When mounted in a drop of water on the slide under the 
