EXPLANATION 7 



Surrounding the seed-vessel are the stamens, whose 

 more or less threadlike filaments are tipped by pollen- 

 bearing anthers. In some plants the stamens and pistils 

 are in separate flowers. 



Surrounding the stamens is the corolla of several or 

 many petals, which are separate or are more or less united. 

 In some flowers the corolla is lacking. When the petals or 

 lobes of the corolla are alike in size and shape the flower 

 is regular, when some are unlike others the flower is 

 irregular. 



Surrounding the corolla is the calyx of several sepals, 

 separate or variously united. In some species both calyx 

 and corolla are lacking. 



The seed-vessels show great variety in form. The more 

 common are: the capsule, a dry fruit opening by valves 

 or slits; the legume, the fruit of the pea family, usually 

 opening along two sides; the achene, a small, dry, one- 

 seeded fruit, as in the composites; the berry, in which the 

 entire wall of the seed-vessel becomes pulpy ; and the drupe, 

 in which the outer part of the wall becomes pulpy and the 

 inner part becomes hard and encloses the seed, as in the 

 plums. 



Arrangement of Flowers 



Flowers are solitary, or are in spikes, racemes, or pani- 

 cles, which are terminal, i. e., terminating the branches, 

 or axillary, i. e., borne in the leaf-axils, where the leaf 

 joins the stem. The spihe is a narrow inflorescence in 

 which the flowers are sessile on the flowering-stem. 



In the raceme each flower is on a small stalk, the pedicel. 

 In the umbel the main axis is so contracted that the 

 flower-stalks apparently rise from a common center, as in 

 the carrot family. The panicle is a branched inflorescence 

 icL which the flowers are stalked. 



