OLOSSAJty OF 



Nl'CLeits : the btxly of the oviile within the coats (Fig. 172, k). 

 Emukyo-sao : the large cell in the nucleus in wliich tlie young 



plant is developed (Fig. 172, ein). 

 Chalaza : the jjortion where the two coats are blended 



together (Fig. 172, c). 



Kinds of Ovule. 



ORTHOTROPor.s : wlirn the ovnle is erect, and the micropyle is 

 as far as possible from the funiculus or point of attach- 

 ment (Fig. 172). 



Anatr«)1*Oi:s : when the ovule is comiilctely invertt'd or bent 

 upon itself so as to bring the niicrojjyle close to the point 

 of attachment (Fig. 173). In this case the funiculus 

 becomes fused with the primine on one side, forming the 

 raphe (Fig. 173, r). 



CAMPVU>TROl»ors : when the ovule is half bent over (,Fig. 174). 



Fertilization. 



Ovules are converted into seeds by the action of pollen upon 

 them. Pollen grains fall upon the stigma which is moist 

 and retains them. The grains begin to grow as shown 

 in Fig. luO, the inner coat being protruded as a slender 

 tube which makes its way down through the stjde into 

 the ovar>', and then through the micropyle of the ovule, 

 finally attaching itself to the surface of the embryo-sac, 

 and carrying the contents of the iiollen-graln with it. 

 Presently growth begins inside the embryo-sue, and soon 

 the embryo is forme<l. It is the presence of the embryo 

 which marks the distinction lietween an ovule and a seed. 



In most cases the ovule is fertilized by pollen brought 

 from another flower of the same sixicies (cros.s-fertiliza- 

 tion), because very coinmonly the fioUon of its own flower 

 is ready either too soon or too late to bo of u.se ; that is, 

 the pollen and the stigma in the same flower do not com- 

 monly mature at the same time. Plants are 



Kntomophilowi, when they depend n|)on in.sects to 

 rarry the pollen from flower to flower, and 



Anfimophilaus, when this service is performrd by the 

 wind. 



THE FRUIT. 

 Deflnition. 



The fniit is the rif»ened pistil together with any other part, 

 such as the calyx or receptacle, which nuiy be adherent 

 to it. If there are no such adherent parts the fruit is a 

 tno' fruit, consisting wholly of the rij^ned ovary with 

 the seeds ; otherwise it is a jtsfwlocarp or spur imis fruit, 

 as in Apple, Strawberry and Kose. 



Flff. 174. 



