1922] WILLAMAN & SANDSTROM—SCLEROTINIA 301 
HYDROGEN JON CONCENTRATION 
ol lll AML 
TITRATABLE ACIDITY 
Ttid alt tht 
SPECIFIC GRAVITY 
Ady AL san 
| I 
: an ae 
9 
$ StF 96 CSF | al Ged el “a8 4 
Stage 7 pis P a 
FRESH souwp ROTTED 
Fic. 5.—Graphs in which data for Px values, sere acidity, and specific 
gravity are assembled to bring together resistant and non-resistant varieties of plums 
for direct comparison; varieties 9, 16, and 30 are resistant ai table I and fig. 3). 
OXALIC ACID IN JUICE 
: Vai amore |e 
° 
mg ee TANNIN IN JUICE 
250 430 
200 
10 
vo 
$0 
2 «et Pe deci al vay | | L 
Fell Sad Git et lh a edt Sn vd Sus dude “woes 9 C SF dod 3 
FRESH SOUND norriD 
Fic. 6.—Graphs in which data for oxalic acid and tannin are assembled to bring 
together resistant and non-resistant varieties of plums for direct comparison (see 
table I and figs. 3, 4). 
