532 



BOTANY 



PART II 



the bud. The inflorescence is in some cases terminal (Metroxylon), and 

 the individual perishes with the development of the fruits. More 

 often the inflorescences are axillary. When young, they are enclosed 

 by a massive resistant sheath, the spathe ; this bursts open and permits 

 of the unfolding of the simple, or more usually branched, inflorescence. 



The individual flowers are as a rule unisexual and constructed on the ordinary 

 monocotyledonous type ; P 3 + 3, A 3 + 3, in the male flowers, and P 3 + 3, G (3), 

 in the female flowers. In Cocoa their distribution is moncecious. Fig. 528 repre- 

 >riits the inflorescence of (,'</<</.< /(//<//'/". still partly enclosed by the spathe. The 



male flowers are crowded on the 

 terminal brandies of the inflores- 

 cence, while the female flowers 

 are considerably larger and stand 

 singly lower down. The ovary, 

 which is here composed of three 

 united carpels, becomes, as a 

 rule, unilocular in the fruit, 



Fin. .")-".. ClK-l.l-Iillts (III till' Stem. 



i;. 530. Coco-nut after partial re- 

 moval of the fibrous exocarp. (After 

 WAGNER, reduced.) 



since only one carpel develops further. The ripe fruits (Fig. 529) are borne in 

 small numbers on each inflorescence. Each consists of a coarse, fibrous exocarp, 

 which contributes to the buoyancy of the fruit in water, and thus leads to the 

 wide distribution of this palm on tropical coasts, and a hard endocarp on which 

 the sutures of the three carpels can be plainly distinguished. At the base of each 

 carpel a germinal pore is present in the endocarp (Fig. 530), but only the one in 

 relation to which the embryo lies, remains permeable. The endosperm forms a 

 thick layer within the endocarp ; it is rich in fatty substances and produces the 

 COPRA of commerce. The space within the endosperm is partially filled with fluid, 

 the "milk" of the coco-nut, which is possibly of service in germination. The 

 embryo on germination develops a massive absorbent organ which grows into 

 the cavity of the fruit and serves to absorb the reserve materials. Fig. 531 shows 

 the general habit of Coco-nut palms. 



Differences are, however, found within'the order. In Arcca catechu, the fruit 

 developed from a similar ovary to that of Cocos is a berry, the exocarp becoming 

 partly fibrous and partly succulent. The white endosperm is here of stony 



