Chap. IL CLEMATIS. 49 



clasped the stick, was that of a man standing by a 

 column, who throws his arm horizontally round it. 

 With respect to the stem's power of twining, some 

 remarks will be made imder G. calyeina. 



Clematis Sieboldi. — A shoot made three reyolutions 

 against the sun at an average rate of 3 hrs. 11 m. The 

 power of twining is like that of the last species. Its 

 leaves are nearly similar in structure and in function, 

 excepting that the sub-petioles of the lateral and 

 terminal leaflets are sensitive. A loop of thread, 

 weighing one-eighth of a grain, acted on the main 

 petiole, but not until two or three days had elapsed. 

 The leaves have the remarkable habit of spon- 

 taneously revolving, generally in vertical eUipses, in 

 the same manner, but in a less degree, as will be 

 described under C. microphyEa. 



Clematis calyeina. — The young shoots are thin and 

 flexible: one revolved, describing a broad oval, in 

 5 hrs. 30 m., and another in 6 hrs. 12 m. They followed 

 the course of the sun ; but the course, if observed long 

 enough, would probably be found to vary in this species, 

 as well as in all the others of the genus. It is a rather 

 better twiner than the two last species : the stem some- 

 times made two spiral turns round a thin stick, if free 

 from twigs ; it then ran straight up for a space, and 

 reversing its course took one or two turns in an 

 opposite direction. This reversal of the spire occurred 

 in all the foregoing species. The leaves are so small 

 compared with those of most of the other species, that 

 the petioles at first seem ill-adapted for clasping. 



