1900 | BRIEFER ARTICLES 199 
into the best position for photosynthesis, and appears to be a definite 
physiological adaptation. The downward turning of the head which 
occurs later may be produced by the weight of the developing seeds, 
but it must not be forgotten that this is also a decided advantage. 
The whole large disk filled with seed is thus well protected from the 
rain, the dying bracts, no longer useful for food manufacture, forming 
a roof which sheds water very successfully. This position also permits 
Fic. 7.—Wild HH. annuus, 7 A.M. July Fic. 8.—The same group of plants as in 
"7, 1899, showing eastward nutation. fig. 7, at 7 P.M. of the same day, showing 
the more prominent westward nutation. 
the seed to fall readily to the ground and at the same time affords 
considerable protection from birds, many of which are very fond of 
the seed. 
During the summer of 1899 some observations were again made 
upon the wild variety of H. annuus, in Clay county, Kansas. There 
's nothing new to add to the report in my former paper, but a number 
of photographs are presented showing the character of the nutation. 
Fig. 7 shows a group of plants at seven o’clock in the morning of 
Julygr7, and fg. 8 represents the same group at seven o’clock of the 
evening of the same day. The more pronounced nutation in the eve- 
ning is very apparent. ig. g shows a field of young sunflowers aaa 
at sunset on June 27. The plants in the foreground show the striking 
