THE FLOWER. 



65 



much reduced in size, with the stigma in some cases hardly 

 at all developed. These flowers do not secrete uectar, or 

 emit any odor; from their small size, as well as from the 

 corolla being rudimentary, they are singularly inconspic- 

 uous; consequently insects do not visit them, nor could 

 they find an entrance if they did. Such flowers are, there- 

 fore, self-fertilized, yet they produce an abundance of seed. 

 In several cases the young cap- 

 sules bury themselves beneath the 

 ground, and the seeds are there ma- 

 tured." — (Darwin.) 



83. After fertilization an embryo 

 is developed in the embryo-sac ; the 

 ovary enlarges, and the ovules or 

 seeds grow to the normal size. The 

 embryo is the initial plantlet (Fig. 

 149, J), and consists of an axis, called 

 the caulicle (Lat. eaiilis, stem) ; one Pi"^ 

 end of which, in germination, grows jz. 

 downwards, and is called the radi- 

 cle ; the other end grows upwards, 

 and is terminated by a bud, which 

 is called the plumule ; and of 

 seed-leaves, called cotyledons 

 (Gr. kotula, cup). In case of the Grasses, Sedges, Lilies, 

 .Flags, etc., there is a single cotyledon to each embryo, 

 and the group of plants to which they belong is said to 

 be monocotyledonous (Fig. 150). In case of the 

 Pea, Bean, Buttercup, Eose, Ash, Maple, Oak, Chestnut, 

 etc., there are two cotyledons to each embryo, and the 



Fig. 149. A dicotyledonous seed (Bean) in diiFerent stages of germination : rd, 

 radicle ; j5/, plumule ; coi^ cotyledons ; hy, hypocotyledonary portion of stem. 



5 



