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INTRODUCTION TO BOTANY 



its apex. The other organs are borne in successive cycles 

 farther and farther away from the tip of the receptacle. But 

 in many of the most highly specialized kinds of flowers the 

 receptacle, as previously stated, bears a sort of tubular or cup- 

 like extension, on the rim of which the petals and the stamens 

 are so borne as to surround the ovary (fig. 114, A) ; or the 

 extension of the receptacle may rise to the top of the ovary, 



so that the petals 

 (if present) and the 

 stamens appear to 

 grow out of its top 

 surface (fig. 114, JS). 

 When the ovary 

 stands wholly above 

 the surrounding 

 floral whorls, it is 

 said to be superior, 

 or the flower is 

 hypogynous (mean- 

 ing " under the 

 ovary"). When the 

 ovary is encircled 

 by the other floral 

 whorls, it is said to 

 be half-inferior, or 

 the flower is perigy- 

 nous ("around the 

 ovary "). When the petals and stamens appear to spring from 

 the top of the ovary, it is said to be inferior, or the flower is 

 epigynom (" upon the ovary "), as in the evening primrose, 

 (fig. 115). 1 



123. Floral diagrams. Lengthwise sections of the flower may 



be represented by simple diagrams like that of figure 102, B. 



These are convenient to show the relation of the other whorls 



to the pistil. Cross sections like those of figure 116 show the 



1 The suffix gynous refers to the ovary only by a fanciful figure of speech. 



FIG. 115. Flower cluster of evening primrose 



