14 INTRODUCTION. 



Decurrent (Fig. 34.), running down the stem or branch so 

 as to form a leafy border. 



Peltate or Shield-shaped (Fig. 35.), when the stalk is in- 

 serted into the middle of the leaf. 



Leaves are Simple or Compound. A Simple Leaf is one 

 which consists of a single piece, whether sessile or stalked. A 

 Compound Leaf is one which consists of several pieces con- 

 nected by insertion into a common footstalk. In simple leaves 

 there are to be considered the general form, the terminations, 

 the margins, the surface, the substance, and the duration. 



With respect to form, Simple Leaves are 



Orbicular, when the length and breadth are equal. (Fig. 35.) 



Roundish, when the length and breadth are nearly equal. 



Egg-shaped or Ovate (Fig. 36.), longer than broad, the 

 base broader than the end. 



Inversely egg-shaped, or obovate, longer than broad, the end 

 broader than the base. 



Oval or Elliptical (Fig. 37.), the length greater than the 

 breadth, but both ends alike rounded. 



Oblong, the length three or four times greater than the 

 breadth. 



Spathulate (Fig. 38.), circular at the end, and tapering to- 

 wards the base. 



Wedge-shaped or Cuneate (Fig. 39.), broad at the end, and 

 tapering towards the base. 



Rhombic or Diamond- shaped, approaching to a square. 



Lance-shaped, Spear-shaped, or Lanceolate (Fig. 40.), ob- 

 long and narrow, tapering towards each end. 



Linear (Fig. 41.), very narrow, with the edges parallel. 



Needle-shaped, Acerose, or Acicular, linear and evergreen. 



Triangular (Fig. 42.), flat with three angles. 

 Quadrangular, with four angles. 

 Quinquangular, with five angles. 



Kidney-shaped (Fig. 43.), roundish, with the base hollowed 

 out. 



Heart-shaped (Fig. 44.), egg-shaped, with the base hollowed 

 out. 



Arrow-shaped (Fig. 45.), triangular, hollowed out at the 

 base, with the angles pointed. 



