LEAVES 



IV. Take a leaf of the common " English Ivy," which is 

 also netted-veined, and compare it with the one just studied, 

 noting the similarities and differences. Notice also : 



1. The different shape of the leaf blade. It is said to be 



palmately-lobed. 



2. Make a rough sketch. 



V. Take a leaf of the Lily of the Valley and study the 

 venation, noticing : 



1. The central stouter vein. 



2. The other veins running approximately parallel to it. 



3. The absence of conspicuous anastomosing veins to form 



a network. 



4. Such a leaf as that of the Lily of the Valley is said to be 



parallel-veined. 



5. Make a sketch to show this kind of venation. 



VI. Take a leaf of the Calla Lily and study the venation. 

 Notice : 



1. The central vein or rib. 



2. The side veins running out from it. 



3. This leaf is also said to be parallel-veined and represents 



simply a different arrangement. 



4. Draw a sketch to illustrate this method of venation. 



VII. Netted-veined leaves are usually associated with ex- 

 ogenous stems, dicotyledonous embryos, and the parts of the 

 flower arranged in fours or fives. 



Parallel-veined leaves are usually associated with endoge- 

 nous stems, monocotyledonous embryos, and the parts of the 



