PLATE ioi 
Middle part of shoot of Bryophyllum calycinum, showing results of inoculation with 
Bacterium tumefaciens (hop strain) oil March io, 1920. The needle was set in horizon¬ 
tally just below the lower left petiole. As the tumor developed it twisted the leaf and 
shoot and caused the bud above it to grow. This axil was the only one on the plant 
that developed any shoots. Other plants not photographed behaved in the same way. 
The shoots show secondary branching (under the arrows) and enormous enlargement at 
the base. At XX leaves were broken off. Root anlage at R. Photographed June 17, 
1920. 
