94 MORPHOLOGY 



are said to be didynamous — g, as in tulsi. When 

 there are six free stamens, of which four are long 

 and two short, they are said to be tetradynamous 

 —f, as in Mustard. 



Adhesion of Stamens. — When the stamens ad- 

 here to the coroUa-tube, so that they seem to arise 

 from the latter, they are said to be epipetalous (see 

 fig. 215, V), as in Datura and most flowers with a 

 gamopetalous corolla. When the stamens adhere to 

 the pistil, they are said to be gynandrous — e, as in 

 akanda, isher-mul (see also figs. 116 and 208, st.a.), 

 and rasna. 



Dehiscence of Anther. — Pollen-grains or micro- 

 spores, as mentioned above, lie enclosed in the two 

 anther-lobes within four pollen-sacs. As the anther 

 matures the two pollen-sacs in each lobe of the anther 

 usually coalesce to form one sac, and the pollen- 

 grains still lie enclosed within the sac. The pollen- 

 grains, which are the male cells, must be brought 

 into contact with the female cell, which in its turn 

 lies enclosed within the pistil. Without this contact 

 of the male cell with the female one, and their sub- 

 sequent fusion, no seeds are produced, and without 

 seeds, as you know, there can be no reproduction. 

 For the purpose of reproduction, therefore, the first 

 step that is necessary is the dehiscence or bursting 

 of the wall of the pollen-sacs so as to set free or shed 

 the pollen-grains; the next step is pollination, or 

 carrying the liberated pollen-grains to the pistil which 

 bears within it the female cell; and, lastly, fertiliza- 

 tion, or the fusion of the male cell with the female 

 cell, which results in the formation of seeds. With 

 regard to dehiscence of the anther, the following 

 modes are common : the anther, or rather the wall of 

 the pollen-sac, dehisces either (i) longitudinally 



