10 ELEMENTS OP STRUCTUEAL BOTANY. 



12. You are now to try and procure a Buttercup whose 

 flowers, or some of them, have withered away, leaving 

 only the head of carpels on the 

 receptacle. The carpels will have 

 swollen considerably, and will now 

 show themselves much more dis- 

 Fig. u. Fig, 15. tinctly than in the flower which 

 we have been examining. This is owing to the growth 

 of the ovules, which have now become seeds. Remove 

 one of the carpels, and carefully cut it through the 

 middle lengthwise. You will find that the seed almost 

 entirely fills the cavity. (Figs. 14 and 15.) 



This seed consists mainly of a hard substance 

 called albumen, enclosed in a thin covering. At 

 the lower end of the albumen is situated a very 

 small body, which is the embryo. It is this 

 which developes into a new plant when the seed '^'^s- 16. 

 germinates. 



13. We have seen, then, that our plant consists of 

 several parts : 



{Vj. The Root. This penetrates the soil, avoiding 

 the -light. It is nearly white, is made up of fibres, from 

 which numUers of much finer fibres are given ofi", and is 

 entirely destitute of buds and leaves. 



(2). The Stem. This grows upward, is coloured, 

 bears foiiage-leaves at intervals, gives off branches from 

 the axils of these, and bears flowers at its upper end. 



(3). The Leaves. These are of two sorts : Foliage- 

 leaves and Flower-leaves. The former are sub-divided 



Fig. 14.— Kipe carpel of Buttercup, 



Fig. 15. — Section of same. 



Fig. 16. — Section of seed showing the small embryo. All much magnified. 



