484 
Journal of Agricultural Research 
Vol. V, No. 11 
Table IV .—Presence of active protozoa in different soils at different temperatures when 
the moisture conditions were favorable 
Lab¬ 
ora¬ 
tory 
No. 
Kind of soil. 
Mois¬ 
ture 
con¬ 
tent. 
Relative 
amount 
of 
moisture 
(in opti¬ 
mums). 
Temperature 
of 4 
incubation. 
Presence of active protozoa.a 
8 to 12 
hours 
after 
inocu¬ 
lation. 
30 to 36 
hours after 
inocula¬ 
tion. 
Third day 
after 
inoculation. 
Fourth day- 
after 
inocula¬ 
tion. 
1202 
1204 
1302 
1304 
1402 
1404 
1212 
Z214 
1312 
I3U 
1412 
1414 
1222 
1224 
1322 
1324 
1422 
1424 
1232 
1234 
1332 
1334 
1432 
1434 
1242 
1244 
1342 
1344 
1442 
1444 
Greenhouse. 
-do. 
Orchard. 
-do. 
Field. 
-do. 
Greenhouse. 
.do.... 
Orchard... 
_do. 
Field. 
_do. 
Greenhouse 
_do. 
Orchard... 
.do. 
Field. 
_do. 
Greenhouse 
_do. 
Orchard... 
_do. 
Field. 
_do. 
Greenhouse. 
.....do... 
Orchard. 
.do... 
Field.... 
.do... 
Per ct. 
28.88 
36.66 
26. 52 
29*05 
21.83 
25.86 
33-66 
26. 52 
29-05 
21.83 
25.86 
28.88 
33-66 
26.52 
29.05 
21.83 
25.86 
28.88 
33-66 
26. 52 
29.05 
21.83 
25.86 
28.88 
33-66 
26. 52 
29.05 
21.83 
25.86 
2 
2^ 
2 
2X 
2 
2% 
2'A 
2 
2^ 
2 
2K 
2 
2^ 
2 
2% 
2 
2% 
2 
2 A 
2 
2X 
2 
2H 
2 H 
2 
2X 
2 
2 Vz 
°C. 
5 to 7... 
5 to 7... 
5 to 7... 
5 to 7... 
5 to 7... 
5 to 7... 
S.C.+ 
F.t.. 
16 to 17. 
16 to 17. 
16 to 17. 
16 to 17. 
16 to 17. 
16 to 17. 
22 tO 24- 
22 to 24. 
22 tO 24. 
22 tO 24. 
22 tO 24. 
22 tO 24. 
33 to 33. 
32 to 33. 
32 to 33. 
32 to 33. 
32 to 33- 
32 to 33. 
s.c.t 
F.t.. 
s.c.t..., 
F.t. 
S.C.t., 
F.t..., 
s.c.t. 
F.t..., 
S.C.t F.t 
S.C.t.... 
S.C.t.... 
S.C.t F.t 
S.C.t F.t 
s.c.t.... 
F.t. 
F.t. 
S.C.t F.. 
Outdoor 
t e mpera- 
ture. 
do 
. .do.. 
. .do.. 
..do.. 
. .do.. 
S.C.t F.t 
S.C.t.... 
S.c.t F.t 
F.t. 
S.C. 
F.t. 
F.t. 
S.C.ttt F.tt. 
S.C.t F.t— 
S.C.t. 
S.C.t F.t... 
F.tt. 
S.C.tt F.tt. 
S.C.tt F.tt. 
S.C.t. 
S.C.t F.t. 
S.C.tt F.tt. 
vS.C.t. 
F.t. 
S.C.t. 
S.C.tt L.C.t F.t 
S.C.Tt F.ttt. 
S.C.ttt L.C.t F.t 
S.C.tt. 
s.c.t. 
s.c.t. 
S.C.tt F.t. 
S.C.+ F.tt. 
S.C.t F.t.. 
S.c.t F.t.. 
F.t 
S.C.t F.t 
F.t 
F.t 
S.C.t 
S.c.t 
F.t 
S.C.t F.tt 
S.C.tt F.t 
F.t 
F.t 
S.C.tF.tt 
F.tt 
F.tt 
S.C.t 
s.c.t 
s.c.t 
s.c.tt 
F.t 
F.t 
S.C.t F.t 
S.C.ttt 
S.c.t L.C.f 
F.t 
F.t 
S.C.t F.tt 
L.C.t F.t 
S.C.t F.tt 
a S.C.=small ciliates, L.C.«large ciliates, F.=flagellates, A.=amebse, t=few, tt=several, fff=many. 
The data presented in Tables III and IV again point to the fact that 
the supply of sufficient moisture is the limiting factor which influences 
the presence of protozoa in the active state in the soil, while the tem¬ 
perature, the presence of organic matter, and the soil structure seem 
to be only secondary factors. 
On examining Table IV it becomes apparent that the temperature 
influences the period of excystment, in that a higher temperature may 
encourage a more rapid excystment of a greater number of protozoa and 
that the physical character of the soil may be more or less influential 
in the movement of the organisms in the soil; yet if the moisture content 
is not high enough, the protozoa will not be present in the active state. 
To find out whether protozoa were always present in the active state 
in water-logged soils, samples of six soils, three greenhouse and three 
field soils, which were kept in the laboratory for some time, were put 
into small bottles, water-logged, and the bottles plugged with rubber 
stoppers to prevent evaporation, and then allowed to stand in the labo- 
