200 BOTANICAL GAZETTE [MARCH 
effect of a large field of plants all bending to the west. The tipping 
of the heads to the east or northeast is at times very prominent. /ig. 
70 shows a small patch of plants with the heads in this position. 
Fic. 9.—A field of wild H. annuus, just at sunset, June 27, showing the pro- 
nounced westward nutation in young plants. 
The writer knows of no better plant for the study of the light rela- 
tion of leaves than Helianthus annuus, and it can be made an object 
of great interest to the young student. 
Some observations were also made upon #. petiolaris. It was 
observed to nutate go° west in the evening, before the heads came into 
G. 10.—A patch of wild H. annuus at noon, August 23; the heads tip toward 
the northeast. 
bloom, the nutation being nearly as marked as in A. annuus. On 
opening, the heads generally tip and the direction is usually to the 
northeast, at least for the terminal ones. But this movement is much 
oe prominent than in #. annuus.—Joun H. SCHAFFNER, Columbus, 
to. 
