ON DROSERA ROTUNDIFOLIA 9 
condition attained 3 hours and 15 minutes after stimulation is 
shown in e. 
Unbending commenced immediately. TABLE I shows that 
this resulted from elongation of the concave side and contraction 
of the convex side. The region of elongation is at first near the 
base in Segment 7, which lies opposite the lower portion of Seg- 
ment 6 on the convex side. This region gradually extends 
apically. The contraction on the convex side is mostly confined 
to the base, and it is moreover relatively slight, being only one 
fourth the amount of elongation on the concave side. Fic. 2 
shows the result of these alterations inlength. Since the reaction 
commences near the base, this portion is the first to straighten; 
SC a 
Fic. 2. Side views of the tentacle shown in Fic. 1 in the process of unbending. 
x 22. a-e, successive stage in the expansion; f, the tentacle at the completion of 
the reaction. 
as successive portions on the concave side further removed from 
the base elongate, the straight part of the pedicel lengthens. In 
unbending the tentacle is therefore curved in a different manner 
than during bending. In the latter case, the principal curve is 
near the base, in the former, nearer the apex. A comparison of 
