THE FLOWER. 



65 



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

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

 emit any odor ; from their small siae, 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 eases 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, /), and consists of an axis, called 

 the caulicle (Lat. caulis, 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, Rose, Ash, Maple, Oak, Chestnut, 

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



Fig. 149. A dicotyledonous seed (Bean) in different stages of germination : rd^ 

 radicle ; //, plumule ; cot^ cotyledons ; Aji, hypocotyledonary portion of stem. 



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