Flowers and their Parts 



151 



In Satyrium the bracts become more and more like the 

 foliage leaves farther down on the stem. Bracts are modified 

 leaves. Are all flowers subtended by bracts ? 



Relation of Flower Parts. — Just as bracts merge into 

 leaves, so the sepals may become quite leaf-like, and there are 

 green Roses and Dahlias in which the petals have taken on the 

 appearance of leaves. Usually stamens and pistils look very 

 unlike leaves, but here the garden flowers come in as teachers. 



A canna flower is interesting. Above the ovary are three 

 small sepals ; then three narrow-pointed petals. The showy 

 parts come next, and on one of them an anther locule is 

 formed ; the other locule is replaced by a petal-like part. It 



Fig. 148.— Spathe of 

 Zantedeschia <2thiop- 

 ica, Spreng {Richar- 

 dia africana, Kunth), 

 surrounding spadix. 



Fig. 149. — Stages of transition between the petals 

 and stamens of Rosa centifolia.^ (From Thom^ 

 and Bennett's "Structural and Physiological 

 Botany".) 



must be a stamen. It is the only one which bears an anther, 

 but from the position of the others we call them sterile 

 stamens, or staminodia. 



Water-lilies and garden flowers which double, show all gra- 

 dations of stamens that have become transformed into petal- 

 like bodies. 



The pistil at the very centre of the flower has been so pro- 

 tected and has its one special work to perform, the bearing of 

 seeds, that it is seldom altered so as to make evident its 

 kinship to the leaves. The carpels of Sterculia appear like 



^ It would probably be more in accordance with the order of develop- 

 ment were the order of the nurnerals — 1-6 — reversed. 



