OF THE STAMENS. 



57 



Fig. 160. Frankenia, showing the five stamens (around the one style, which haa 

 three stigmas at top). 



Fig. 161. Stamen (adnate) of Morning-glory. 



Fig. 162. Same, enlarged, with pollen-grains discharged:/, filament; a, anther, 

 — two-lobed ; c, top of connectile. 



Fig. 163. Buttercup. Fig. 164. Same, cut across. 



Fig. 165. Iris, cut across (extrorse). 



Fig. 166. Amaryllis,— versatile. Figs. 167, 168. Larkspur,— innate. 



103. But dehiscence takes place very variously. When all 

 regular, it is a chink running lengthwise along the outer edge, 

 as you see in this stamen of a Buttercup (Fig. 163). But 

 here, in this stamen of Iris (Fig. 165), it appears on the back 

 of the anther (looking towards the petals), and we say that 

 the anthers are extrorse^ that is, turned outwards. A term 

 of opposite meaning is introrse^ denoting that the lines of 

 dehiscence turn inwards towards the pistil, or at least do not 

 turn outw^ards. For example, the antliers of the Yiolet 

 (Fig. 173). 



104. Moreover, other modes of dehiscence besides chinks 

 are occasionally found. The anthers of Berberis, Sassafras, 

 &c. (see Figs. ITl, 172), open by lids hinged at the top. The 



103. When is the anther said to be extrorse ? introrse ? 

 10k Can you distinguish the opercular and iiorous dehiscence? 



3* 



