46 LEAF-CLIMBERS. Cuap. II. 
observed, in order to see what amount of difference 
in the manner of climbing existed within the same 
genus; and the differences are considerable. 
CiemaATIs.—C. glandulosa.—The thin upper inter- 
nodes revolve, moving against the course of the sun, 
precisely like those of a true twiner, at an average 
rate, judging from three revolutions, of 3 hrs. 48 m. 
The leading shoot immediately twined round a stick 
placed near it; but, after making an open spire of 
only one turn and a half, it ascended for a short space 
straight, and then reversed its course and wound two 
turns in an opposite direction. This was rendered 
possible by the straight piece between the opposed 
spires having become rigid. The simple, broad, ovate 
leaves of this tropical species, with their short thick 
petioles, seem but ill-fitted for any movement; and 
whilst twining up a vertical stick, no use is made of 
them. Nevertheless, if the footstalk of a young leaf 
be rubbed with a thin twig a few times on any side, 
it will in the course of a few hours bend to that side; 
afterwards becoming straight again. The under side 
seemed to be the most sensitive ; but the sensitiveness 
or irritability is slight compared to that which we 
shall meet with in some of the following species ; thus, 
a loop of string, weighing 1°64 grain (1062 mg.) 
and hanging for some days on a young footstalk, 
produced a scarcely perceptible effect. A sketch is 
here given of two young leaves which had naturally 
caught hold of two thin branches. A forked twig placed 
so as to press lightly on the under side of a young 
