122 PLANT STRUCTURES 
are grouped in circles (whorls) at certain points 
of the stem, as in the Bedstraws; often in oppo- 
site pairs, arranged criss-cross, as in the Syca- 
more; most frequently in a series of spirals. The 
result in all cases is the same—it allows of as great an 
Fic, 22,._LEAF OF WEINMANNIA TRICHOSPERMA. }. 
interval as possible between any leaf and the one 
immediately below or above it, and gives to all an 
equal share of light. The indenting of leaves, as in 
the Sycamore, or their division into separate seg- 
ments, as in the Ash and Horse Chestnut, is of un- 
