CORN" BREEDING 
37 
of 16 standard Iowa varieties of corn. From 7,000 to 12,000 self- 
pollinations have been made each year as a basis for selection, and 
P£D/M£EWMB£/?SO£W££M/!OWS MOWN /NTf/EY&lfiS STATED 
/920 /92/ /922 
/923 
/924 
/92S 
4-/ 
4-/-/* 
4-/2 
* Z ^4-22* 
* J ^4-3-2* 
,4-4-f k 
4-4C4-42* 
x 4-4-3* 
4-5—4-5-/* 
4-6-/* 
462* 
+*<! 
4-7< 4 ' 7V 
,4-8-/* 
'4S( 
X 4S2 
4/2-/ 
■4/2-/-/ —4-/-2-/-H 
4-/-2-/-Z* 
^'' i/ ° < ^4-/-2-/-3-2 
•4-/22* ^4-/2-/4—4-'-2-/-4-f 
/4-3-/-H* 
4-3-H 4-4-3H-2* 
^43-/-/-3* 
4-4-/-N* 
4-4-N-2-. 
■4-4-/-Z — 4-4-/-2-Z* 
>44-/-3 —4-4-/-3-Z* 
■44-H <"***"* 
^ <t?;fi7 4 ' 7 - / ' 2 - N 
4-7-/3* 
■4-7-Z-22' 
•4-3-2-/-/* 
,482-/-2* 
■4S-2-/-3* 
•4-32-/ ^4-82-U* 
4-S2-/-5* 
'4-822 — 4-822-/— 4-8-2-2-H 
^ Fig. 7. — Outline of the pedigrees within a single family (No. 4) of selfed lines during six 
generations. The pedigree numbers are of the ear rows grown from selfed ears in the 
years stated. Each ear row from which no seed was selected for continuing the lines 
is marked with an asterisk 
more than 3,000 cross-pollinated ears, representing 480 combinations 
between 80 unrelated lines, were obtained for use in the first com- 
parison of crosses, 
