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BOTANICAL GAZETTE 



[may 



the stem erect, while at 7 or 8 P. M. the maximum westward nutation 

 occurs. The plant begins to assume the erect position soon after sun- 

 set, and is usually quite erect by 19 or 11 p. m., and remains so until 



approaching sunrise. 



Outside of the Compositae I find a nutation, though less marked, 

 in Amaranthus, particularly in the younger plants, and in many of the 



Fig. i\, — Bidens frondosa, taken with camera facing east. All plants facing the 



camera and the sun. 



Leguminosae. Doubtless it is to 



be found in many other families. 



Mel 



M 



folium are striking in nutation- Melilotus alba, for example, is par- 

 ticularly interesting, as the marked nutation strikingly affects the 

 landscape as seen in going and returning from a day's drive. 



It is my purpose here simply to call attention to the diurnal bend- 

 ing or nodding of the stem. In addition to this there are of course 

 very complicated changes in leaf position, — Frank Lincoln Stevens, 



Agricultural and Mechanical College, Raleigh. N. C. 



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■ I 'J' rn 



