1913] GODDARD—SOIL FUNGI 285 
tures of investigation V were made. This solution contained, in 
addition to the usual culture constituents, 400 mg. of ammonium 
nitrate. From this solution 50 Cc. were accurately measured 
from a burette and then diluted to 2 50 cc. in a volumetric flask. 
Then 50 cc. of this solution was taken for analysis. This contained 
80 mg. of ammonium nitrate. The results of these analyses are 
given in table V. 
TABLE V 
Blank by nitrate method, o. 56mg. N; control with other constituents of the 
medium, but no ammonium nitrate, o.7omg. N; calculated percentage of N in 
ammonium nitrate, 35.04 






; : Deviation 
N obtained | Calculated | Difference 
No. Material less blank | amount (b—a) Rete eaten 
mg. mg. mg. percentage 
a b c d e€ 
OE RESET GeO ae Ae Seat 
Tt | 400 mg. dry NH,No,.....| 138.6 140.1 1.5 34.6 0.4 
2 | 400 mg. (duplicate) ..... 139.2 140.1 0.9 34.8 | 0.2 
ERs Wiasemresree a ne | | 
N obtained | 
less blank 
and control : 
3 | 80mg. (socc. of solu- 
SPN es eg Re 27.79 28.04 0.25 34-7 0.3 
4 | 80 mg. (duplicate) ...... 27.79 28.04 0.25 34.7 0.3 


These results seem to show that the method is sufficiently 
accurate for detecting any appreciable gain in nitrogen in the cul- 
tures containing ammonium nitrate. 
INVESTIGATION I 
As previously stated, cultures were made in large test tubes, 
each containing 25 cc. of the culture medium. This medium had 
the following composition: 
Water (ammonia-frec). .... 1000.00 CC 
Rock candy (pure), M/so 17.107 gm 
Monopotassium phosphate, M/roo 2... 25... 1.361 gm 
Magnesium sulphate, M/s00.................-.. ©. 241 gm 
Calcium carbonate, M/ido0< 60.3) ©. 100 gm. 
“or controls, ammonium nitrate was added to the above as follows: 
maGnatin titrabe Sori pegekk Duel, eae ©. 360 gm. 
The following 11 different species were used for the inoculations: 
Mucor ambiguus, M yceliophthora sulphurea, Coccospora agricola, 
