16, 6 Trelease: The Growth of Rice 605 
of intersections (R1) represents combinations in which 0.1 of 
the total osmotic concentration is due to primary calcium phos- 
phate; the second row (R2) represents those having 0.2 due 
to primary calcium phosphate, etc.; while the apex of the trian- 
gle (R8) has 0.8 due to primary calcium phosphate. Similarly, 
the line forming the left-hand margin of the triangle represents 
combinations in which 0.1 of the osmotic value is due to am- 
monium sulphate, while the angle at the extreme right represents 
a combination having 0.8 due to this salt. Likewise, the line 
R8 Ci 
R5 /Cl 
One part — part 
(NH,),80, R4/C1 K, SO, 
NENT ALS. 
in Id NS 
SUAS AVAS 
RAPFCy 2 3 4 5 6 ts 
One part Ca (H, PO,), 
Fic. 1. Culture numbers and osmotic proportions of the three salts. 
at the right-hand margin denotes combinations in which 0.1 of 
the total osmotic value is due to potassium sulphate, while the 
angle at the extreme left denotes a combination in which 0.8 
are due to this salt. Following the method employed by Shive, 
each culture is designated by the row number and the number 
of the culture within the row—for example, R1C5. The salt 
mixture for this culture has 0.1 of its total osmotic value due 
to primary calcium phosphate, 0.5 due to ammonium sulphate, 
and 0.4 due to potassium sulphate, 
