CHAP. IV. CIRCUMNUTATION OF FLOWEK-STEMS. 223 



ClRCUMNUTATION OF FLOWER-STEMS. 



We did not think it necessary to make any special 

 observations on the circumnutation of flower-stems, 

 these being axial in their nature, like stems or stolons ; 

 but some were incidentally made whilst attending 

 to other subjects, and these we will here briefly give. 

 A few observations have also been made by other 

 botanists. These taken together suffice to render it 

 probable that all peduncles and sub-peduncles cir- 

 cumnutate whilst growing. 



Oxalis carnosa. The peduncle which springs from the thick 

 and woody stem of this plant bears three or four sub-peduncles . 



Fig. 91. 



Oxalis carnosa : flower-stem, feebly illuminated from above, its circximnuta 

 tion traced from 9 A.M. April 13th to 9 A.M. 15th. Summit of flower 

 8 inches beneath the horizontal glass. Movement probably magnified 

 about 6 times. 



A filament with little triangles of paper was fixed within the 

 calyx of a flower which stood upright. Its movements were 

 observed for 48 h. ; during the first half of this time the flower 

 was fully expanded, and during the second half withered. The 

 figure here given (Fig. 91) represents 8 or 9 ellipses. Although 

 the main peduncle circumnutated, and described one large and 



