THE LEAVES. 



123 



When this flattening is extensive, so that the petiole becomes 

 thin and leaf-like and the blade is wanting, it functions as a 



foliage leaf (fig. 144). Not infrequent- 

 ly, the petiole is winged, as in the orange. 

 It may be entirely wanting, in which 

 case the blade arises directly from the 



base, as in most grasses 



(ng. 137). 



154. 3. The leaf 

 blade.- -To this part of 

 the leaf the word " leaf ' 

 itself is frequently ap- 

 FIG. i 4 i. plied. In general, the 



FIG. 140. Stipules of Polygonum forming a i r IJo^p jc c O hrnaHlv 



sheath, o, above the sheathing leaf base s, of the 1Cai 



cut-off leaf y; cc, the stem; ca, an axillary winge( J as to b e t hj n 



shoot. Natural size. After Jbrank. 

 FIG 141 -Leaf of 77^,// with clasping base. flt b t R 



Natural size. After Prantl. 





FIG. i 4 o. 



FIG. 142. FIG. 143. 



FIG. 142. Shoot of Uvularia, showing pcrfoliate leaves below. About half natural 



size. After Gray. 

 FIG. 143. A shoot of wild honeysuckle, showing upper leaves connate-perfoliate. 



About half natural size. After dray. 



