THE GENOTYPICAL RESPONSE OF THE PLANT 233 
collected at Lund in 1919 and grown on the same bed as the former. 
Besides the very great difference in thickness the maritima leaf is 
found to be isolateral, while the inland leaf is found to have only 
one layer of palisades on the lower side. 
Fig. 10 represents an individual from one of the clones cultivated 
in 1922 (viz. field no. 3), and fig. 11 shows an individual from 
another clone (field no. 2). This latter was crossed in 1920 with 
the inland type. The F,-generation was found to be uniform and 
intermediate as to shape and thickness of leaf segments. The plants 
were as erect as the inland type, and, like the latter, had a single 
main axis, but 
the crown of the 
plants was very 
bushy.’ Fig. 12 
illustrates one of 
these F,-plants. 
They all died in 
the autumn, thus 
being annual like 
the inland type. 
The F,-plants 
obtained in 1922 
from the crosses 
between F;,-indi- 
viduals (the 
plants were 
found to be Fig. 12, Matricaria inodora. A Fı-plant from a cross 
between the inland type and the shore 
type represented in fig. 11. 
wholly self-steri- 
le) is at this mo- 
ment still in the rosette stage. However, segregation is very evident. 
As to the shape of the leaf segment there are (out of a total of 163 
plants) 28 short and blunt (like the maritima parent), 56 short and 
pointed, 58 elongated, 17 long segmented (like the inland parent), and 4 
very long and narrow. The segregation is evidently polyhybrid show- 
ing transgression in one direction. The grouping of the individuals 
as to leaf thickness is rather peculiar; there are 9 very thick and fleshy 
(transgressions), 62 thick-leaved (like the maritima parent), 59 inter- 
mediately thick and 33 thin leaved (like the inland parent). The 
segregation, although probably polyhybrid, is presumably disturbed 
by modificatory influences. It will be followed up closely when flow- 
