50 



GENERAL PRINCIPLES. 



These are either distinct or more or less united by their 



edges. The united portion is called the calyx-tube, and 



the free points the segments. 



The corolla (B, fig. 34,) is within the calyx, and is the 



colored, showy part of the flower ; its divisions are called 



petals. 



Stamens (C, fig. 34), immediately within the petals, are 

 the male organs of plants. The 

 delicate, thread-like filament (A, 

 fig. 35), supports, on its extremity, 

 the anther (B, fig. 35). This 

 contains a powdery substance, the 

 pollen, which is liberated when 

 the anther is mature. 



The pistil (D, fig. 34 and fig. 

 36,) is the female organ, and stands 

 in the center of the flower. It 

 consists of the ovary, at its base 

 (A, fig. 36), which contains the 

 ovules or rudiments of seeds. 

 The style (B, fig. 36) is the 

 elongated portion, and the stigma 

 (C, fig. 36,) is the portion that 

 receives the fertilizing powder 

 (pollen) from the anthers. The 

 stigma is usually rounded like a 

 knob, but frequently it is incon- 

 spicuous. 



Flowers may be deficient in any 



of these organs except the anthers, ovary, and stigma. 



These are indispensable to fructification, and must be 



present in some form or other, or the flowers will be 



barren. 



2d. Sexual Distinctions. The fact that the two sexes, 



or sexual organs, the stamens, and pistils, are, in certain 



species, united on the same flower, and in others on dif; 



Fig. 37. FLOWERS OF THE 

 FILBERT. 



