STRUCTURAL BOTANY. 



59 



Cot IX. 



The carpellarj scales and naked ovules of the Gym- 

 nosperms have been already sufficiently described in § 45. 



109. The stamens vary in number. A flower with a 

 solitary stamen is monandrous. The terms diandrous^ 

 triandrous, tetrandrous^ pentandroics^ etc., and jpolyan- 

 droioSy signify furnished with 2, 3, 4, 5, many stamens. 

 Compare § 57. When the stamens are very numerous, 

 they are arranged in several rows. 



Stamens take their origin from floral leaves in the same 

 way as pistils. The filament represents the petiole, and 

 the anther the blade of a leaf. The blade curved in, until 

 each of its edges unites with the midrib, forms a 2-celled 

 anther. The usually well-marked stripe, which extends be- 

 tween the anther-cells, answering to the midrib of tlie 

 leaf, is the connective or connectile. The anther is the 

 essential part of the stamen (see § 33), and commonly it 

 is 2-lobed and 2-celled — rarely 4- or 1-celled. It is the 

 function of the anther to produce pollen, and discharge 

 it at maturity. 



With regard to their position, the stamens are hy- 

 pogynous^ when they spring from the receptacle below the 

 ovary or ovaries (Cut X., Fig. 1) ; per igy nous ^ when they 

 are inserted on the calyx around the ovary (Fig. 2) ; epipe- 



talous, when they are fixed on the corolla ; epigynous^ 



when they stand on a level, answering to the summit of the 

 ovary so as apparently to spring from the top of this or- 



