118 TENDEIL-BEARERS. Chap. III. 



night and rises during the day, moving, also, during 

 the day in a crooked course to the west. The tip of 

 the tendril is highly sensitive on the lower surface ; 

 and one which was just touched with a twig became 

 perceptibly curved in 3 m., and another in 5 m. ; the 

 upper surface is not at all sensitive ; the sides are 

 moderately sensitive, so that two branches which were 

 rubbed on their inner sides converged and crossed each 

 other. The petiole of the leaf and the lower parts of 

 the tendril, halfway between the upper leaflet and the 

 lowest branch, are not sensitive. A tendril after curling 

 from a touch became straight again in about 6 hrs., and 

 was ready to re-act ; but* one that had been so roughly 

 rubbed as to have coiled into a helix did not become 

 perfectly straight until after 13 hrs. The tendrils re- 

 tain their sensibility to an unusually late age ; for one 

 borne by a leaf with five or six fully developed leaves 

 above, was still active. If a tendril catches nothing, 

 after a considerable interval of time the tips of the 

 branches curl a little inwards ; but if it clasps some 

 object, the whole contracts spirally. 



Smilace^e. Smilax aspera, var. maculata. Aug. 

 St.-Hilaire * considers that the tendrils, which rise in 

 pairs from the petiole, are modified lateral leaflets ; 

 but Mohl (p. 41) ranks them as modified stipules. 

 These tendrils are from 1J to If inches in length, are 

 thin, and have slightly curved, pointed extremities. 

 They diverge a little from each other, and stand at 

 fiist nearly upright. When lightly rubbed on either 



* < 



Lemons de Botanique,' &c, 1841, p. 170. 



