FORMS OF COMPOUND LEAVES. 



A pedate leaf, with 

 compound leaflets 

 folium pedatum ; 

 foliis composilis. 



Example: I he Maid- 

 en hair Adiantum 

 pedatum. A very com- 

 mon plant in the neigh- 

 bourhood of Philadel- 

 phia. 



Fig. 73. PEDATE. 



a b 



The most singular of 

 all the various leaves, are 

 those of the pitcher plants. 

 The pitcher of the Nepen- 

 thes (74, c) is provided with 

 a perfect lid or cover, which 

 is closed in dry weather, as 

 if to prevent evaporation, 

 and open when it is rainy 

 or damp. It has been sug- 

 gested, that these pitchers 

 were designed as reservoirs 

 in which water is stored 

 for the occasional use of 

 the plant in extremely dry 

 weather. 



When the petiole be- 

 comes dilated and hollowed 

 out at its upper end, the 

 lamina being articulated with and closing up its orifice, as in 

 Sarracenia (fig. 74, a), and Nepenthes (fig- 74, c), it is called 

 a pitcher, or a&cidium ; if it is enclosed and is a mere sac, as in 

 Utricularia (fig. 74, 6), it is called ampulla. 



The surface of a leaf may be ribbed or nerved, having fine elevations, 

 running from one extremity to the other, without branching ; or 



Veined, having prominent divisions near the base, and finer and smaller 

 as they extend over the leaf, as in the mullein ; or 



Wrinkled, rvgose, rough, or corrugated, like the leaf of the sage ; or 



Fig. 74. LEAVES OF PITCHER PLANTS. 



