ON Drosera rotundifolia 7 



The figures given in the tables are in hundredths of a milli- 

 meter. Measurements were made on the drawings, which were 

 checked by the direct measurements. The time at the head of 

 the first column shows when the gland was stimulated. The 

 column to the right of the heavy line shows the first indication of 

 unbending. The segments were marked off naturally by the 

 presence of glandular hairs on the two flattened surfaces. They 

 are numbered from the apex to the base. The segments on the 

 concave side do not always correspond to those on the convex side. 



(c) Experimental Data 



Measurements of the dorsal and ventral sides of a tentacle in 

 the process of bending and unbending are given in Table I. The 

 tentacle was selected from next to the outermost row on a fresh, 

 red, young leaf which was secreting copiously. The leaf had 

 been protected during its development and was not touched, or 

 stimulated in any other way, prior to the experiment. Its reaction 

 is typical of the marginal tentacles on young leaves, unless perhaps 

 it is more than usually vigorous. 



The straight tentacle measured 2.94 mm. in length. The leg 

 of a small house-fly was laid on the gland. One minute and a 



