1921] SCHERTZ—MOTTLING 89 
Fic. 2.—Plants 3 months old: one labeled —NO, grown full time with NOs 
lacking i in eee: solution; one labeled +NO, grown with NO, lacking in nutrient 
<gonton for 2.5 months and one dose of NO, added, after which plants grown for 
re; plants labeled oe PO, and +PO, similarly treated; here PO, was 
jidittaacs lacking or adde 
oe ge 4 months old, during which time solutions containing Mg, 
N, P. Ca, Fe, othing were added to soil in respective pots; effect of addition of N 
shown by poe isles of plant, as well as healthier color of leaves. 
: : + “ 
Mo NO, PO, Ca Fe i @) 
Fic. 4.—Plants similar to those in fig. 3, but grown in pots 1 inch larger 
