32 TWINING PLANTS. Cuap. I. 
(DicoryLepons, continued.) 
(a distinct shoot, very 
H M. 
April, 2nd circle was made in 12 20 \ young, on gameplan’) 
” 3rd ” ” ” be 7 30 . 
n this latter circle, 
the semicircle from 
the light took 5 hrs. 
ne oy mm «8 93 m., and to the 
light 2 hrs. 37 min.: 
difference 2 hrs. 46m. 
Aristolochia gigas (Aristolochiacese) moves against the sun. 
. Me 
July 22, Ist circle was made in . 8 0 (rather young shoot) 
” 23, 2nd ” ” ” . 7 15 
” 24, 3rd ” ” ” . 5 0 (about) 
In the foregoing Table, which includes twining 
plants belonging to widely different orders, we see 
that the rate at which growth travels or circulates 
round the axis (on which the revolving movement 
depends), differs much. As long as a plant remains 
under the same conditions, the rate is often remarkably 
uniform, as with the Hop, Mikania, Phaseolus, &. The 
Scyphanthus made one revolution in 1 hr. 17 m., and 
this is the quickest rate observed by me; but we shall 
hereafter see a tendril-bearing Passiflora revolving 
more rapidly. <A shoot of the Akebia quinata made a 
revolution in 1 hr. 30 m., and three revolutions at the 
average rate of 1 hr. 88 m.; a Convolvulus made two 
revolutions at the average of 1 hr. 42 m., and Phaseolus 
vulgaris three at the average of 1 hr. 57m. On the 
other hand, some plants take 24 hrs. for a single 
revolution, and the Adhadota sometimes required 
48 hrs.; yet this latter plant is an efficient twiner. 
