BOTANY. 27 



When both organs arc found in the same flower, this is hermaphrodite ; it is 

 unisexual^ or diclinous, if but one of the two be present. A flower bearing 

 stamens alone, is stamini/erous ; and pislilliferoiis, when only the ))istil is 

 present. The absence of one of the organs is due to abortion or fion-devdop- 

 ment. When the same plant, with unisexual flowers, embraces both kinds, it 

 is monoecious ; if the two sets of organs are borne on different individuals, the 

 species is dioecious. 



The stamens which arise within the petals and in one or more whorls on the 

 thalamus, constitute, when taken together, the androecium or male apparatus. 

 Their normal position is below the whorl on the pistil ; they are then hi/po- 

 gynous, and without adhesion to the walls of the calyx. AVhcn united to the 

 petals, they are epipetalous. If attached to the sides of the calyx, they be- 

 come perig'i/nous ; and if united both with the surface of the calyx and of the 

 ovary, they are epigynous. These are important terms in classification. 

 Plants bear the general title o^ thalaniijiorcc when the parts of the corolla and 

 androecium are independent of each other, and all the whorls inserted directly 

 upon the torus. They are calyciflora. when the petals are separate, and the 

 stamens inserted directly on the calyx : coroUiflorcB when the united petals 

 bear the stamens. 



The number of stamens varies from one to many hundreds, arranged in a 

 variable number of whorls. When there is but one whorl, the stamens are 

 usually equal in number to the sepals or petals, and are arranged opposite to 

 the former, and alternate Avith the latter ; the flower is then isoste?nonous. 

 When the stamens are unequal in number to the sepals or petals, the 

 flower is anisostemonous. When there are twice as many stamens as 

 sepals or petals, the flower is diplostenionous ; if more than this, polyste- 

 tnonous. The number of stamens is generally an exact multiple of the 

 number of floral envelopes. By an arrest of development in which the 

 number of stamens is less than that of sepals or petals, the flower is 

 nieiostemoyious. 



When the numl>er of stamens is less than 20, they are called definite, and 

 the flower is oUgandrous : over this number they are indefinite or polyan- 

 drous, and are marked 00. The number of definite stamens is indicated by 

 prefixing the Greek numeral to androus ; thus a flower with one stamen is 

 monandrous ; with two, diandrous ; three, triandrou,s ; four, tetandroiis ; 

 five, pentandrous ; six, he.vandrous ; seven, heptandrous ; eight, octandrous ; 

 nine, enneandrous ; ten, decandrous, &c. 



A stamen consists of two parts, one contracted and thread-like, answering 

 to the petiole of the leaf, and called the filament ; the other, a broader 

 portion, representing the blade of the leaf, and called the anther, which 

 contains a powdery matter termed jjollen. The anther is the essential male 

 organ. When there is no filament, the anther is sessile. The filament may 

 vary much from its usual thread-like form. It sometimes puts on a petaloid 

 appearance ; is occasionally subulate or awl-shaped, and again, clavate or 

 club-shaped. When the filament is bent or jointed it is geniculate. Cer- 

 tain appendages are sometimes seen at the bases of filaments which are 

 then said to be appendiculate or stnmiose. The filaments occasionally 



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