5i6 
Journal of Agricultural Research 
Vol. XXIV, No. 6 
other side with consequent injury and this may explain the discrepancy. 
Also, in his experiments the epidermis treated may not have been so 
free from tiny abrasions. 
TablS V .—Leaves of apple treated on the upper or the lower surface to determine the 
relative injury 
Variety. 
Chemical. 
Strength. 
Injury. 
Upper. 
Uower. 
Transcendent. 
Wealthy. 
McIntosh. 
YellowTransparent 
Calcium 
arsenite. 
1-1,000. 
Very slight.... 
None. 
Very slight.... 
None. 
Very slight. 
Very bad. 
Moderate. 
Very slight. 
Transcendent. 
Wealthy. 
McIntosh. 
Yellow Transparent 
Calcium 
arsenite 
plus 
soap. 
1-1,000 
(14.4 gm. 
in 2 li¬ 
ters). 
fNone. 
_do. 
.... do... 
_do. 
Very slight. 
Do. 
Do. 
None. 
Transcendent. 
Wealthy. 
McIntosh. 
YellowTransparent 
Calcium 
arsenite. 
1-500. 
Very slight.. . . 
None. 
Very slight.. . . 
None... 
Slight. 
Do. 
Very bad. 
Slight. 
Transcendent. 
Wealthy. 
McIntosh. 
YellowTransparent 
Calcium 
• arsenite 
plus soap. 
1-500 (14.4 
gm. in 2 
liters). 
fNone. 
_do. 
_do. 
-do. 
Slight. 
Moderate. 
Very slight. 
Partly defoliated. 
Transcendent. 
Wealthy. 
McIntosh... 
YellowTransparent 
Sodium 
arsenite. 
1-1,000. 
fNone. 
Very slight. 
None... 
Very slight.. . . 
Moderate. 
Very bad. 
Bad. 
Do. 
Transcendent—.. 
Wealthy.. 
McIntosh. 
YellowTransparent 
Sodium 
• arsenite 
plus soap. 
1-1,000 
(14.4 gm. 
in 2 li¬ 
ters). 
fNone. 
-do.. 
Very slight. 
None. 
Slight. 
Moderate. 
Partly defoliated. 
Defoliated. 
Transcendent. 
Wealthy. 
McIntosh. 
YellowTransparent 
Sodium 
arsenite. 
1-500. 
[Slight.. .. 
None. 
Moderate. 
Slight. 
Bad. 
Very bad. 
Partly defoliated. 
Very bad. 
Transcendent. 
Wealthy. 
McIntosh. 
Yellow Transparent 
Sodium 
• arsenite 
plus soap. 
1-500 (14.4 
gm. in 2 
liters). 
[Very slight. 
None. 
Slight. 
None. 
Very bad. 
Partly defoliated. 
Do. 
Defoliated. 
Whether the under surface of apple leaves is more susceptible to in¬ 
jury because of the greater prevalence of stomata or because of a thinner 
or more permeable cuticle is yet to be determined. We are inclined to 
the latter view. 
To determine if this greater protection of the upper epidermis is found 
also in other plants the leaves of a dozen different shrubs and tr^ on 
the college campus were painted with sodium arsenite and soap in dif¬ 
ferent strengths. The procedme was the same as described for apple 
on page 515. These plants are as follows; Alder, barberry (common, 
green), birch (white), box elder, buckthorn (English), chokecherry, dog- 
