SCIENCE PRIMERS. 



[xvn. 



1 06. When fully formed the anther-cells open to 

 allow the pollen to escape, in most plants by longi- 

 tudinal slits on the face (towards the pistil) ; but in 

 some by lateral slits (buttercup), or dorsal ones (iris). 

 In the heath order the anthers open by terminal pores 

 (Fig. 48 b\ which in the bilberry (Fig. 48 a) are at the 

 end of long tubes. In the barberry (Fig. 48^:) they open 



Bilberry. 



Heath. 



Barberry. 



Mistletoe. 



FIG. 48. Stamens of. a, bilberry; b, heath ; c, barberry; d, mistletoe: all 

 much enlarged. 



by oblong lids that fall away ; and in the mistletoe 

 (Fig. 48^) by many holes, each of which is a pocket 

 full of pollen. 



FIG 49. Transition from stamen a, to petal />, and to sepal c, in double rose. 



