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cut surface the two kinds of tissue and the two lines of contact 
between them. On this surface a callus formed from which 
uds arose. If a bud arose entirely from the portion that was 
nightshade the branch was purely a nightshade in its charac- 
teristics; if from a segment of tomato tissue the branch was pure 
tomato. If, however, a branch arose over the line of juncture it 
was composed partly of tomato and an of iota se tissues. 
Such branches were named ‘chim The simpler of these 
show vertical lines of ac ee one side cae tomato 
leaves, flowers and fruits, while the other side of the branch 
bears the vegetative and floral organs of the nightshade. Leaves 
on the exact line of juncture are part tomato and part nightshade 
in character. In a cross section of the main stem the tissue of 
each component occupies a segment or sector. Such branches 
and the plants grown from them are therefore known as sectorial- 
chimeras. In such an association of two kinds of cells, each 
sort retains its own individuality and the vegetative and floral 
structures of each side are readily identified. None of these 
purely sectorial-chimeras exhibit the intermediate character ob- 
served in the supposed graft-hybrids 
In 1909, however, Dr. Winkler obtained an adventitious branch 
which when propagated produced plants having leaves, flowers 
and fruit which were different from either those of the tomato or 
of the nightshade. This new form was named Solanum tubing- 
ense. The general appearance of this type is intermediate be- 
tween the tomato and the nightshade. The leaves are simple, 
sharply aves and often lobed much like the leaflets of the 
tomato plant. The stems and leaves are hairy like the tomato. 
The pene and calyx are larger than those of the nightshade 
but smaller than those of the tomato. The fruit is slightly larger 
than the fruits of the nightshade, which are much smaller than 
the fruits of the variety of the tomato ae in the Man 
of the fruits of this type are sterile but several generations of 
seedlings grown from seed have been pure nightshade and are not 
like the plants Solanum tubingense from which they were derived. 
In continuing his experiments Dr. Winkler soon obtained 
the three other-types of tomato-nightshade chimeras shown in 
