90 



COLLEGE BOTANY 



minate group the buds begin to bloom at the base of the axis, 

 while in the cymose or determinate group the buds at the tip 

 of the axis are the first to bloom. 



In the raceme the flowers are arranged along an elongated 



axis, and there is a small leaf- 

 like .structure or bract at the 

 base of each flower. Common 

 examples are the lily of the 

 valley, the wild cherry and the 

 currant. Sometimes the ra- 

 cemes are branched and there- 

 fore known as compound ra- 

 cemes, as in the case of the false 

 Solomon's seal. 



The panicle is a loose, com- 

 pound, somewhat irregular 

 raceme, such as is found in the 

 oat and some of the grasses. 



The thyrsus is a compact 

 pyramidal panicle, such as is 

 found in the lilac and the horse 

 chestnut 



The corymb is a raceme 



. . --- 



pulpit; (a) bulb; (6) leaf and spathe; (c) with a SOmewhat shortened a 

 flo 



FIG. 69. Indian turnip or Jack-in-the- 

 . ulpit; (a) bulb; (6) leaf and spathe; (c) 

 spathe open to show spadix and flower near 



an( j 



w hi c ] 1 the peduncles 



(i.e., stem for each flower) of the lower flowers are elongated 

 so as to bring all the flowers on about the same level, as in the 

 case of the mountain ash. 



The umbel has such a very short axis that the peduncles ap- 

 pear to arise from the same point, as in the case of the milkweed 

 and the wild carrot. We also find the compound type of umbel. 



