66 



OBJECT LESSONS IN BOTANY. 



The central organ (or organs) is the pistil, 

 to notice the form of the stamens. 



We now propose 



156 15T 158 169 



A leaf (Fig. 155), a sepal (Fig. 156), a petal 

 (Fig. 157), a stamen (Fig. 158), and a pod (pis- 

 til, Fig. 159) of Draba arabizans, placed side 

 by side for comparison. 



100. The stamen may 

 be compared to the leaf. 

 Its slender, thread - like 

 stalk is the filament, an- 

 swering to the petiole of 

 the leaf (f,p)- Its head 

 {a) is the anther, answer- 

 ing to the blade. More- 

 over, the anther contains 

 within its cells many dust- 

 like particles called pol- 

 len. When the cells burst the pollen escapes. Thus it ap- 

 pears that the stamen consists of three members. See them 

 illustrated in this figure (161) of a stamen of the Morning- 

 glory. 



101. The filament is usually of a thread-like form (as its 

 name, from the Latin filum, a thread, implies), longer than 

 the anther, and more or less elastic. But the filament is no 

 more necessary than the stem of a leaf, and is often wanting. 



102. The anther is an oblong body at the top of the fila- 

 ment, consisting of two hollow lobes joined to each other 

 and to the filament by the connectile (c), which answers to the 

 midvein of the leaf. The two lobes are usually marked along 

 their outer edge by a seam, which at length opens into the 

 cells. This opening, however it takes place, is called the 

 dehisoenee. If there be no filament, the anther is sessile. 



^^. How many kinds ? Situations of the two kinds respectively ? ' 



100. How does the stamen compare with the leaf? Specify the three mem- 

 bers of the stamen. 



101. Describe the filament. 103. The anther; the dehiscence. 



