6o FLORAL LEAVES 



stamens, or bright-coloured bracts. Occasionally the petals 

 further allure insects by manufacturing honey — for example, 

 the little' pockets at the base of the Buttercup-petals are honey- 

 manufacturing organs — nectaries — (figs. 60, 61 n). Finally the 

 petals may serve as a receptacle and hiding-place for the honey 

 poured out by the nectaries — e.g. spur of the Violet. In other 

 words, the corolla is concerned in securing insect visits : accord- 

 ingly, when the seeds begin to form in the flower, the corolla is 

 no longer required, and it speedily withers. 



PERIANTH. 



When the perianth consists of two or more whorls of members 

 which are all alike, the latter are termed perianth-leaves. For 

 instance, Tulips and Hyacinths have perianths composed of 

 two whorls of floral leaves which are all similar, and cannot be 

 differentiated into three sepals and three petals. The perianth 

 may be brightly coloured {petaloid), as in Tulips, Lilies, and 

 Hyacinths ; or it may be green {sepaloid). If the perianth- 

 leaves be separate, they are said to be polyphyllous — e.g. Tulip ; 

 if they form a coherent tube the perianth is gamophyllous — e.g. 

 Hyacinth (fig. 213). 



Naked flowers (figs. 132, 148). — Flowers may be devoid 

 of sepals — e.g. some Compositse; or without petals — e.g. 

 Clematis; finally, they may possess no perianth whatever, in 

 which case they are said to be naked — e.g. the stamen-bearing 

 flowers of the Hazel and the Petty Spurge, and the flowers of 

 Arum maculatum. Such flowers, consist solely of one or more 

 stamens or carpels, or both of these, inserted upon a receptacle. 



ANDK(ECIUM. 



The whole collection of stamens of a flower constitutes the 

 andrxcium. 



A stamen usually consists of two parts, the filament and the 

 anther. Occasionally the filament is absent, and the anther is 

 consequently sessile. More rarely the anther is absent, and the 

 sterile stamen thus formed is termed a staminode. The anther 

 generally consists of two halves or lobes, and each half has two 

 pollen-sacs in which the pollen-grains are lodged (fig. 85). 

 Occasionally an anther represents half a complete anther and 



