44 



THE FLOWER. 



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

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

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

 the summit. 



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

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

 only at their apex, where there is a passage left through both, 

 called the foramen. The outer integument is called the 2Jriminc, 

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

 (Fig. 11; 8.) 



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

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

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

 wliich at this early period has nof traces of the embryo (18). 



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

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

 nucleus of the o\aile, the ckalaza. 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). This ap- 

 pears to be effected in the 

 following manner. At the 

 proper season, the anthers 

 discharge the pollen con- 

 tained in their cavities, 

 thi'ough their dehiscence 



FIG. 12. — 1, Section of the upper part of the style Or porCS, iutO thc air. Some 

 of the snap-dragon, the pollen tubes passing down qC if iliiig falls UUOn the 

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

 showing the tubes; 6, pollen of the CEnolhera bienni.";, SUj^ma. 

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



a. The Author of nature makes special provision for the accomplu<hment of 

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

 stamens being lovs:er than the jiistils when the flower is erect, as in die tulip, 

 and shoiier, when it dix)op?, as in several species of tlie lily. In thc mountain 



