136 Plants and their Ways in South Africa 



hermaphrodite. The willows and arums have neither calyx 

 nor corolla. A flower may be reduced to a single stamen or a 

 single pistil, as in Euphorbia. 

 A complete flower has 



(1) Calyx, made up of sepals. 



(2) Corolla petals. 



(3) Stamens ,, ,, filaments and anther. 



(4) Pistil ,, ovary, style, and stigma. 

 A perfect flower has 



(i) Stamens. 

 (a) Pistil. 



Practise making out these whorls in flowers. Find other 

 flowers which are pistillate or staminate. 



FIG. 124. Diagrammatic sections of ovaries : /. the placenta, to which 

 the seeds are attached. A, apocaipous ; B, C, D, syncarpous. (From Ed- 

 monds and Marloth's "Elementary Botany".) A. B, with parietal; C, D, 

 with axile placentation. 



Do not try to remember any of these names until you have 

 seen the parts themselves. 



Different Kinds of Pistils. The long style of Hibiscus 



is necessary to bring the 

 stigma out beyond the 

 stamens. In some Or- 

 nithogalums and in Al- 

 buca the stigma sits 

 directly on the ovary. 

 The style is not in all 

 cases necessary to the 

 pistil. It depends upon 

 the shape of the flower. 

 If a flower has two or more carpels, they generally grow 

 together. A syncarpous ovary may be one-, two-, three-, four-, 

 or many-celled (or uni-, bi-, tri-, quadri-, or plurilocular). 



FIG. 125. I. Marginal placentation. II. 

 Unilocular ovary, with free central pla- 

 centa. (From Edmonds' "Elementary 

 Botany".) 



