44 



THE FLOWER. 



a. The ovule is said to be erect when it grows from the base of the ovaiy 

 ascending, when it grows from a little above the base ; pendulous, when it hangs 

 from the summit of the cavity, and suspended, when it hangs from a little below 

 the summit. 



90. In their early state, the ovules are quite soft, consisting of 

 two sacks or integuments, containing a pulpy mass, and open 

 only at their apex, Avhere there is a passage left tlirough both, 

 called the foramen. The outer integument is called the pri7nine, 

 the other the secundine, and the central pulpy mass the nucleus. 

 (Fig. 11; 8.) 



a. The foramen may be detected even in the perfect seed, by soaking it in 

 water, and then pressing out the fluid thus absorbed, which will be seen to issue 

 from this little orifice. It has an important agency in the fertilization of the seed, 

 which at this early period has no traces of the embryo (18). 



91. The stalk by which the ovule is connected to the pla- 

 centa, is called the funiculus, and its point of attachment to the 

 nucleus of the ovule, the chalaza. Through these the ovule 

 receives its nourishment from the placenta. (Fig- 11 ; 8, 9.) 



} 4. OF THE MUTUAL ACTION OF THE STAMENS AND PISTILS. 



92. The specific use of 

 the stamens and pistils is 

 the fertilization of the 

 seed (57, 58). Tliis ap- 

 pears to be effected in the 

 following manner. At the 

 proper season, the anthers 

 discharge the poUen con- 

 tained in their cavities, 

 tlurough their dehiscence 



FIG. 12. — 1, Section of the upper part of the style Or poreS, into the air. Some 

 of the snap-dragon, the pollen tubes passing down q^ j-(- i^J^i^i^g falls UDOU the 

 between the cells ; 2, 3, 4, 5, various forms of pollen, 

 showing the tubes ; 6, pollen of the ffinothera biennis, SUj^lllcl. 

 one of its tubes descending among the cells of the style. 



a. The Author of nature makes special provision for the accomplishment of 

 this function. Thus the anthers are generally placed above the stigma, the 

 stamens being longer than the pistils when the flower is erect, as in the tulip, 

 and shorter, when it droops, as in several species of the lily. In the mountain 



