26 NOTES ON MICRO-ORGANISMS. 
Before proceeding to consider in brief the chief methods of 
research adopted for micro-organisms, I might make mention of 
some other sources of such organisms, a matter which we have 
as yet treated very generally. Many kinds of Bacteria in various 
stages of development are to be found in the slime that generally 
collects on a dripping water-tap, as also in pipes used for the 
intermittent conveyance of water and other liquids. In such 
slime the following organisms may be seen :— 
Bact. termo. Leptothrix. 
Bact. lactis. Pasteur’s Lactic Ferment. 
Bacc. subtilis. Bact. aceti. 
Spirillum undula. 
And also mould growths. 
Another very fruitful source of organisms is the steep water 
from maltings, which, after a few hours, may swarm with them. 
Such a large quantity of organisms are present on barley itself, 
and so rich is the steep water in phosphoric acid, nitrogen bodies, 
and other matters suitable to the nourishment of Bacteria, that 
the growth of these last is extraordinarily rapid—temperature 
being favourable. I should like to revive the recollection, which 
most here will have, of the unpleasant-looking growth that was 
in former years seen in the river below the sewage outfall at 
Newton Solney during the summer.. I collected some of this 
in March, 1883, and thought I might produce a sketch of it for 
this evening. It consists of a submerged fungus growth, repro- 
ducing by simple division in one direction; and amongst its 
interlaced threads many kinds of Bacteria and some Infusoria 
were lodged, which had probably developed in the mould growth 
as it died off. (Plate III., Fig. 3.) 
Just at present, the air seems to be teeming with organisms, 
and quite lately I have encountered the following, many of which 
may be met with at all times of the year :— 
Nearly all the commoner forms of Bacteria. 
Bacteria producing red, yellow, and blue pigments. 
Clostridium butyricum, Spiromonas volubilis, Bacillus ulna. 
