38 PBAGTICAL GUIDE TO GABDEN PLANTS 



in others, and Darwin has pointed out that pollen from long stamens 

 in one flower is naturally adapted for fertilising the long pistils in 

 another; and the same with the short forms. Many flowers are 

 fertilised by bees and various insects, but many others, like the Pine 

 trees (p. 972), Willows (p. 802), Alders (p. 796), Poplars (p. 803), 

 Birches (p. 793) &c., depend upon the wind to have their pollen blown 

 about and transferred to the ovules (as in the Pines) or pistils (as in 

 the others). 



FOEMS OP FLOWBBS 



Flowers are usually said to be ' regular ' when their sepals and 

 petals are similar as shown in figs. 24, 40, 54, 59, 63, and 66 in the 

 Glossary ; or ' irregular,' when one or more sepal or petal differs in 

 size or shape from the others as shown in figs. 5, 22, 23, 58, 60, and 

 67. The petals may be quite free from each other, when they are 

 called polypetalous (see p. 122), or may be united, when they are said 

 to be gamopetalous (see p. 125). In the Glossary figs. 23, 24, 59, 63, 

 65, and 67 are examples of Gamopetalous flowers, while figs. 5, 40, 54, 

 and 58 are examples of Polypetalous flowers. The stamens and pistils 

 may also be either free or united. These characters are of great use for 

 the purposes of classification, and are more systematically detailed at 

 p. 120. 



THE INFLOEBSCBNCE 



The way in which flowers are borne is termed the inflorescence. 

 Flowers may be at the ends of the branches or in the axils of the leaves, 

 and may have stalks (peduncles) branched or unbranched forming 

 racemes, panicles, corymbs, umbels, or cymes &c. ; all of which terms 

 are explained and illustrated in the Glossary (p. 1) . When without stalks 

 they may form spikes, as in the Plantain, or heads, as in Clover, or 

 catkins, as in the Birch. There are various modifications of these, as 

 in the Arum Lily, where the flowers are in a fleshy spike (spadix) 

 enveloped in a large and showy leaf called a spathe. 



THE FRUIT 



In popular language the term ' Fruit ' is very vaguely used. 

 Strictly speaking, the ripened carpels, whether hard or soft, constitute 

 the fruit, or, in other words, the seed vessel or ovary. All flowering 

 plants which produce seeds enclosed in an ovary are termed Angio- 

 sperms (see p. 121) and include both Dicotyledons and Monocotyledons. 



