no TA NIC A L TEJii/a. 



37 



The sepals differ less in api)e!iraace from ordinary 

 leaves than any of the oilier parts. The petals resemble 

 foliage-leaves in shape, but are mostly bright-coloured 

 instead of green, and they are often sweet-scented. 

 Sepals and petals together are pt'otec five organs, and they 

 also serve to attract insects. 



Stamens are leaf-forms in which the filament answers 

 to the petiole, and the anther to the blade, as shown in 

 Fig. 21G. 



Carpels are loaf-forms folded lengthwise more or less 

 completely, as shown in Fig. i?l7. 



Stamens and carpels are essciiUdl organs, and are 

 directly concerned in the production of seed. 



FLORAL DIAGRAMS. 



By a floral diagram is meant the plan of a flower as exhibited 

 in a cross-section. It should show tlio number and relative 

 position of all the floral organs. Tiio position of sepals, 

 petals, and stamens is commonly easy to (ix, but the true 

 position of the carpels presents a little more difficulty. The 

 ovary must be cut aci-oss with a sluirp knife while some 

 other organ (saj^ the calj^x) is still in position, and the 

 relative situation of the carpels must then be carefully 

 observed. The aestivation of calyx and corolla may also be 

 shown to advantage in a floral diagram. 



A number of examples of these diagrams are given in tlie 

 margin, and the pupil should make the construction of such 

 diagrams a regular part of his work. 



Fig. 215) is a diagram of a Mint flower. 



Fig. 219 " " '' Leguminous flower. 



Fig. 220 •• " " Marsii Marigold. 



Fig. 221 ^' 



Fi"-. 222 •' 



Fig. 223 •• 



Fig. 224 " 



Fig. 225 •' 



Melon (stuniinute). 

 ■' Melon (pistillate). 



Compo-^itf flower. 

 " Iris. 



I Irass tlower. 



Fi»r. 21B. 



Kip. ?17. 



SC^ 



Fljr. -M". 



FIsr. 219- 



Fife'. JLit. 



Fig. 221. 



Fig. 222. 



FIp.SM. 



tig. r.':\ 



