102 STAMENS. 



and thus stand around the germ, as in rosaceous plants, they are 

 said to be perigynous, (fromperi around, and gynia pistil). 



When a corolla is rnonopetalous, the number of stamens is 

 usually either equal or double, or half that of the divisions of 

 the corolla ; the stamens in such flowers never exceed twenty. 



In polypetalous corollas, the number of stamens may be much 

 greater. When the number of stamens equals the divisions of 

 the corolla, they usually alternate with these divisions. WheA 

 the number of stamens is double the divisions of the corolla, 

 half of the stamens are usually placed in the intervals of the 

 divisions, and the remaining half before each lobe of the corolla, 

 corresponding to the intervals in the divisions of the calyx. If 

 any of the stamens are barren or without anthers, they are 

 those which are placed before the lobes of the corolla. 



In commencing the analysis of flowers according tothe Lin- 

 naean system, you learned that the number of stamens, their po- 

 sition, relative length, and connection, taken either singly or in 

 combination, afford certain and distinctive marks for purposes 

 of classification. 



In the first place we find the stamens differing in number, in 

 different plants ; some plants have but one, some two, and so 

 on till we come to ten ; when they have more than ten, we find 

 the number in the same plant varies, and therefore we cannot 

 depend on the cirumstance of number for further classification. 



We then resort to position, and consider whether the stamens 

 are inserted upon the calyx or not, thus furnishing an eleventh 

 and a twelfth class. 



Inequality in the length of stamens, considered with respect 

 to number, furnishes us with a thirteenth and fourteenth class. 



The connection or union of stamens gives us the fifteenth 

 class, where the filaments of the stamens are united in one set; 

 the sixteenth class where they are in two sets ; the seventeenth 

 where the anthers of the stamens are united. 



The three remaining classes of phenogamous plants are dis- 

 tinguished by the position of the stamens with n-spect to the 

 pistils. In the eighteenth class the stamens stand on the pistil ; 

 in the nineteenth the stamens and pistils are on separate flowers 

 on the same plant ; in the twentieth they are on separate plants ; 

 and in the twenty-first they are invisible. 



We will now proceed to the parts of the stamen ; these are 

 two. The filament and anther. 



The Filament, is so called fromJUui^i, a thread. Filaments 



Divisions of monopetalous corollas usually in proportion to the number of 

 stamens Situation of the stamens with respect to the divisions of the corolla 

 Stamens used for purposes of classification Differ in number In the mode 

 of insertion Stamens differ in length In connection In position with respect 

 * the pistil Parts of the stamens Filament. 



