ig8 THE REPRODUCTIVE ORGANS 



tongues (such as the hawk-moths) are able to extract the 

 whole of it. Insects visiting the flower for honey will at 

 first become dusted with pollen, which may be transferred 

 to an older flower with ripe stigmas. If insects fail, the 

 stigma-lobes curl outwards between the anthers and become 

 self-pollinated an advantage in a species flowering early 

 before many insects are about. As the fruit develops, the 

 scape elongates and carries the ripening capsule above 

 ground, where it dehisces and the seeds are scattered. 



The flower of the Iris (Fig. 136) has three large outer 

 and three small inner perianth-leaves, but has only three 

 stamens, the inner whorl being suppressed, and, as in the 

 Daffodil, they are above the ovary, i.e. they are epigynous. 

 The three styles are transformed into large petaloid lobes, 

 against which lie the stamens. On the under side of these 

 lobes and near the tip is a little flap covering the stigmatic 

 surface. As in the Daffodil, the flowers are enclosed in 

 a large spathe. The petaloid style arms (sy) of the Iris are 

 often applied to the perianth-leaves in such a way as to form 

 a split tube, at the base of which are honey-glands. The 

 difference in size of the perianth-leaves, together with the 

 large petaloid styles, gives to the Iris a striking, and at first 

 rather puzzling, appearance. 



The Orchid flower. Still more puzzling is the flower of the 

 Purple Orchis (Fig. 137). Each flower arises in the axil 

 of a bract and appears to be stalked, but the stalk consists 

 of the inferior ovary and is twisted (2, ov). Hence the flowers 

 are sessile and the oldest are below as in a raceme. 



Such an inflorescence of sessile flowers is called a spike. 



The perianth is epigynous, consisting of six perianth- 

 leaves, one of which (the labellum) forms an alighting 

 stage (Fig. 137, /), while the others form a hood, covering 

 in the stamens and stigmas. From the base of the labellum 

 is produced a tube or spur in which honey is secreted. 

 There is only one stamen (a), the remainder being sup- 



