FOLIAGE LEAVES: THE LIGHT- RELATION 21 
plant is conical,, a form very common in herbs with entire 
or nearly entire leaves. In plants whose leaf blades are 
broken up into leaflets (compound or branched leaves), 
however, no such diminution in size toward the top of the 
stem is necessary (see Fig. 17), though it may frequently 
FIG. 15. A plant showing much-branched leaves, which occur in great profusion with- 
out cutting off the light from one another. 
occur. When a broad blade is broken up into leaflets 
the danger of shading is very much less, as the light can 
strike through between the upper leaflets and reach the 
leaflets below. On the lower leaves there will be splotches 
of light and shadow, but they will shift throughout the 
day, so that probably a large part of the leaf will receive 
light at some time during the day (see Fig. 14). The 
