128 = Self-Incompatibility in Hermaphrodite Plants 
EXPLANATION OF PLATES. 
PLATE Ill, 
All reproduced about twice natural size. 
Nos. 1 and 2 are heads, and 3 the rudimentary achenes.of a third head all resulting from 
self-pollination of a completely self-incompatible plant of chicory; Nos. 4 and 5 are 
heads, and 3 the fully developed achenes of a third head resulting from a compatible 
cross-pollination of same plant on the same date. 
7. Stages in development of achenes in a single head of a feebly ote 
plant to self-pollination; at a, 14 merely rudimentary achenes; at b, 5 achenes of 
sti size but containing no good embryos; at c, one seed with ee “qavelged 
No. é. Series of stages quite as in No. 7. 
No. 9. Achenes from a self-pollinated head of a plant strongly self-compatible. The 
greater number of achenes containing good embryos. No mere rudiments of achenes 
present 
PLATE IV. 
View of chicory in experimental plot showing races of vigorous vegetative growth in the 
1g generation of self-fertilized descent. At the right, field label No. 26 marks the 
Series 10-8-140. To left of label 26 are four rows of two series of the family 12-11-. 
To the extreme left may be seen bags on very tall plants of Series 10-38-37. 
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