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BOTANY 



(1) The Raceme. — Moth mullein is an 

 excellent example. The raceme is a tall 

 flower cluster, bearing short pediceled flow- 

 ers along the sides of its one main stalk. In 

 such an inflorescence you will notice that 

 the oldest flowers are at the base of the 

 cluster. Notice another very important 

 fact, that each flower comes out directly 

 over a tiny green scale or leaf. This fact 

 shows that a flower cluster is a branch which 

 has become changed or modified to bear 

 flowers instead of bearing only green leaves. 



(2) The Spike. — A spike, as may be 

 seen in figure, is simply a raceme in which 

 the individual flowers have lost their pedi- 

 cles, the flowers coming out on the main 

 flower stalk. Examples are plantain, timo- 

 thy grass, and "butter and eggs.'' 



(3) The Umbel. — In this inflorescence 

 the flower stalks spring from near the same 



point on the main flower stalk, like ribs in an umbrella; hence the name. 

 A flat-topped cluster, as in wild carrot or the parsley, is the result. 



(4) The Head. — In the head the long axis of the inflorescence is reduced, and 

 the flower pedicles are also absent. A compact cluster, as in clover, results. 



Spike of Linaria ("butter and eggs"). 



An umbel of milkweed. 



Head of clover. 



(5) Composite Head. — This inflorescence, so often mistaken for a single 

 flower, is found only in the great Composite family, to which so many of our 

 commonest flowers and weeds belong. The daisy, aster, golden-rod, and 

 sunflower are examples of the Compositae. 



The composite head is well seen in an aster or the sunflower. This head 

 has an outer circle of green parts. These parts look like sepals, but 

 in reality are a whorl of bracts. Taken together they form an involiicre. 



