194 STRUCTURAL BOTANY 



The point where the seed is attached to the funicle is 

 called the hilum, and as the ovule from which the 

 seed was developed was anatropous, it follows that 

 the hilum and the micropyle are close together. 



The fruit is called a capsule, i.e. it is syncarpous, dry, 

 and dehiscent. The structure shows very little differ- 

 ence from that of the ovary, but there is an enormous 

 increase in bulk, and some change in shape arid 

 texture, the fruit being thicker in proportion to its 

 length than the ovary, while its tissues have become 

 harder (Fig. 92). The style withers away during the 

 ripening of the fruit. 



The opening or dchiscence of the capsule to set free 

 the seeds takes place by three longitudinal splits, 

 running along the middle of the outer wall of each 

 compartment throughout its whole length (Fig. 92, d). 

 The fruit is thus cleft into three divisions, each repre- 

 senting two half-carpels. The flat, light seeds are well 

 adapted to being scattered by the wind, as they are 

 shed from the dehiscent capsule (Fig. 92). 



i. Germination 



The organ which grows most actively in the early 

 stages of germination is the cotyledon, which elongates 

 to an enormous extent, attaining a length of several 

 inches. The radicle is first pushed out through the 

 micropyle, and then grows down into the earth. The 

 tip of the cotyledon remains immersed in the endo- 

 sperm, and acts at first as an absorbing organ, by 

 means of which the food substances in the seed are 

 taken up by the young plant. The cellulose, starch, 

 and protcids of the endosperm have to be rendered 



