142 Marshall Ward . — On the Character s> or 
path out of the profound wilderness now obscurely darkening 
our maps under the name of bacteriology. The suggestion is 
that botanical bacteriologists and the bacteriologists engaged 
in pathological, hygienic, and other departments of science, 
meet and attempt to determine some international scheme for 
recording the peculiarities of the Schizomycetes they meet 
with, and see if some common ground of agreement cannot be 
attained. 
In conclusion, it is important that all who are interested in 
the study of Bacteria should try to obtain answers to as 
many as possible of the following questions before they 
publish a ‘ new species.’ These questions have been formu- 
lated gradually from the experience of numerous workers 
since Cohn’s time, and I have already shown how the answers 
to them lend themselves to what systems of classification 
we possess. Obviously a complete description of a species 
requires an answer to all of them, and possibly others. 
1. Habitat '. — 
This should be carefully recorded, under such headings as 
Air, Soil, Water (Fresh, Stagnant, Sea, Thermal, Mineral, 
&c.), Milk, Food, Faeces, Dead or living Animals, Plants, &c. 
1 . Nutrient medium : — 
The best pabulum should then be sought for — the organism 
having of course been separated by suitable methods, and 
obtained as pure cultures. It should be stated clearly whether 
it will grow on gelatine, agar, or potatoes, or in broth, 
saccharine liquids, mineral solutions, &c., and its further 
behaviour traced on or in that which suits it best. In 
deciding this point it should be clearly observed whether 
the medium serves best when neutral, or slightly acid or 
alkaline. 
3 o G aseous environmen t : — 
It is important to determine whether the Schizomycete is 
aerobian or anaerobian, as many forms which will not grow 
on or in the above or other media in air, will do so when the 
free access of oxygen is suppressed, partially or entirely. It 
should also be noted whether carbon-dioxide, hydrogen, 
