16 BOTANICAL GAZETTE [JULY 
tion from Orrville, Ohio; station IX, peat soil under cultivation, 
reported as unproductive and ‘“‘sterile,” from Lodi, Ohio; sta- 
tion X, humus soil from the university woodlot (beech-oak-maple- 
elm). The culture media employed for this work were a 1 per 
cent starch peptone water solution; 1 per cent solutions of cane 
sugar, dextrose, and lactose in beef broth; plain bouillon; plain 
and litmus milk; 0.2 per cent nitrate peptone water; Dunham’s 
peptone solution for the indol test; nutrient gelatin and agar. 
Only the generally well known determinations, as of the breaking 
up of carbon and nitrogen compounds and the proportion of the 
various gases evolved, have been made. The chemical analysis of 
the soil samples of stations I to IX is given in tables II and III. 
The culture studies gave the following characteristic results 
after an incubation period of 5 days at 38° C. The action of the 
bacteria on starch shows in several stations the production of an 
inverting ferment by the cultures. The starch is changed into a 
sugar which reacts with the Fehling’s test. In stations III and 
IX there is no action; in stations II and X the conversion is 
carried on a little way and then stops, there being always a red 
or purple reaction with iodine; in station I the starch conversion 
is almost complete; while in stations IV, V, VI, and VII certain 
putrid by-products inhibit in various degrees further conversion. 
Upon the addition of a few drops of potassium iodide, the blue 
color disappears rapidly in stations III, IV, and VI; the hydrated 
iodine is deposited as metallic iodine upon the walls of the test 
tube above the solution. Reduction action is less active in sta- 
tions V, VII, and IX. No decolorization occurs in stations I, 
II, and X. The accumulation of iodine is very strong in the test 
tube of station X and is very likely an indication of the presence 
of oxidizing ferments. With methylene blue the reduction action 
is the same in degree, respectively, in all cases running parallel 
with the iodine action. 
In all stations, with the exception of station I, the action of the 
bacteria on saccharose shows both the conversion of the carbo- 
hydrate into glucose by the inverting ferment, and the production 
of gas and acid. The reaction is strongest in stations VIII and X; 
relatively small in stations V and IX; very little gas is evolved 
