70 



MANUAL OF BOTANY 



lower leaves of the Com Bluebottle ; when the teeth are them- 

 selves divided in a similar manner, it is diiplicato-dentate {fig. 

 120, c). When the teeth are rounded {figs. 119 and 143) the 

 leaf is crenate, as in the Horseradish and Ground Ivy; if 

 these teeth are themselves crenate it is bicrenate (fig. 120, a); 

 when the leaf is minutely crenate it is said to be crenulated. 

 When the margins present alternately deep concavities and 

 convexities iiis, sinuated, as in some Oaks {fig. 121). This kind 

 of leaf may be regarded as an intermediate condition between a 

 toothed leaf and one that is pinnatifid {fig. 113). When the 

 margins are slightly sinuous or wavy, as in the Holly {fig. 

 122), they are said to be wavy or undulated ; the teeth of the 



Fig. 123. 



Fig. 124. 



Fig. 123. Palmate leaf of a species of Passioii-flowev (^Passiflora). 

 Fig. 124. Palmatifid leaf of the Castor-oil plant (Ricinus communis). 



leaves of the Holly are very hard and end in sharp points, 

 forming spines. "When the margins are very irregular, being 

 twisted and curled, as in the Garden Endive, Curled Dock, and 

 Curled Mint, they are called crisped or curled {fig. 98). 



2. Incision. — This term is employed when the margins of 

 the blades are more deeply divided than in the above instances. 

 The divisions are then commonly called lohes. 



When a pinnately veined leaf is deeply divided, and the 

 divisions are very close and narrow like the teeth of a comb 

 {fig. 125), it is said to be pectinate, as in the Water Milfoil ; 

 when the terminal lobe of a pinnately veined leaf is large and 

 rounded, and the lateral lobes, which are also more or less 

 rounded, become gradually smaller towards the base, it is 

 lyrafe, or lyre-shaped, as in the common Turnip (fig. 126) ; 



