Trees, Shrubs and Vines 



The ease (Fig. 6) may be square (a), rounded (b), tapering 

 (c), wedge-shaped (d), pointed (e), or cordate (more or less heart- 

 shaped) (f). 



The apex may be blunt, sharp, taper-pointed, or notched 

 (emarginate) (Fig. 7). 



The edge (Fig. 8) may be entire (a), wavy (b), or variously 

 cut ; when the incisions are small, it is serrate or toothed (c) ; 

 when large, lobed (d) ; with long, sharp projections it is bristle- 

 pointed (e) ; there is great variety in size and form of teeth and 

 lobes ; many leaves are both serrate and lobed. All the varia- 

 tions in form and edge of simple leaves may occur in the leaflets 

 of a compound leaf. 



BLOSSOM 



A complete blossom has four distinctive parts : viz., calyx, co- 

 rolla, stamens and pistil (Fig. g). 



Calyx : this is an outer whorl, usually resembling minute 

 narrow green leaves, either distinct from each other, or more or 

 less grown together, and often with only the apex of each distinct, 

 in the form of a tooth ; the parts of the calyx are called sepals. 



Corolla : this is an inner whorl, usually much larger than the 

 calyx, and variously colored — the showy part of the flower ; the 

 parts, called /^/fl&, are either distinct, or more or less grown to- 

 gether, often separate only at the apex, the lobes showing the 

 number of petals. When the petals are entirely distinct the blos- 

 som is called polypetalous (many-petaled) (Fig. 10) ; when more 

 or less united by their edges, monopetalous (one-petaled) (Fig. 

 11) ; if corolla and calyx are not both present, it is the corolla that 

 is lacking, while the calyx is often colored like a corolla ; the 

 flower is then apetalous (without petals). 



Stamens (Fig. 12) : consisting of filament and anther; the 

 former usually slender and thread-like, enlarged at apex into the 

 anther that contains the pollen ; the filament is sometimes short 

 and stout. 



Pistil (Fig. 13) : consisting of seed-case (a) at base of flower, 

 surmounted by an erect slender style (b) (much like filament of 

 stamen), longer or shorter, and swollen at apex into a stigma (c), 

 for receiving the pollen. 



413 



