INFLORESCENCES 295 



of dicotyledons the parts of the flowers occur in threes and 

 fours. 



This fundamental difference between the flowers of 

 monocotyledons and of dicotyledons gives us additional 

 evidence that these great groups are natural groups. The 

 greater the number of fundamental differences that we find 

 between them, the more remote may we regard their com- 

 mon ancestry to have been. You have now noted of 

 monocotyledons in general that they have one cotyledon, 

 scattered vascular bundles, leaves with parallel veins, and 

 the parts of the flowers in threes or multiples of three. 

 As to dicotyledons in general, you have noted that they 

 have two cotyledons, vascular bundles cylindrically arranged, 

 net-veined leaves, and the parts of the flowers usually in 

 fives or multiples of five, 



63. Inflorescences. Plants differ greatly in the manner 

 in which they bear their flowers. Often you can tell a 

 plant by the manner in which its flowers are arranged. 

 In some you find the flowers on little stems which arise 

 from the axils of ordinary leaves, no particular part of the 

 shoot being devoted to flower bearing. In others, as in 

 some of the lilies, you find single flowers borne on the ends 

 of rather long stems. In most plants, however, you find 

 the flowers in clusters. These clusters are called in- 

 florescences. (The word signifies manner of flowering.) 



In gathering flowers it is often an inflorescence which 

 you break off rather than a single flower. It is so with 

 clover and goldenrod, with butter-and-eggs and queen's 

 lace (wild carrot). The beauty of lily-of-the- valley is in 

 its graceful, drooping inflorescence quite as much as it is 

 in the individual flowers. The brightness of geraniums is 



