IV 



THE STUDY OF THE SHOOT 



49 



5. If half of one conduplicated leaf enfolds another, it is 

 seini-equitant. 



6. If one convolute leaf is rolled around another, it is 

 supervolute. 



EXPT. 34. Cut a transverse section of any leaf- buds met with. 

 Note 



(i) The arrangement of the individual leaves in the bud. 



(ii) The arrangement of the several 

 leaves in the bud. 



(iii) The arrangement of the parts in 

 the buds. Show it by sketches. 



SUMMARY 



A Perfect leaf consists of a sheath, 

 petiole, and blade. If the blade is the only 

 part present, the leaf is said to be sessile, 

 and petiolate when the blade and petiole 

 are developed. 



Stipules are outgrowths at . the base 

 of the leaf. Leaves can be exstipulate 

 or stipulate. 



Venation of leaves two kinds parallel and reticulate. 



Phyllotaxis is the arrangement of leaves on a stem. The common 

 arrangements are alternate, opposite, and whorled. 



Foliage Leaves may be simple or compound. In the former the blade 

 is not divided down to the mid-rib, but in the latter kind the blade is 

 cut up in separate or distinct parts. 



FIG. 69. Transverse section 

 of leaf-bud of Sycamore. 

 (X 4 .) 



Simple leaves may be 

 Lanceolate. Oblanceolate. 

 Ovate. 

 Cordate. 

 Sagittate. 

 Spatulate. 



Obovate. 

 Reniform. 

 Linear. 

 Elliptical. 

 Acicular. 



Compound leaves may be 

 Ternate. Paripinnate. 



Biternate. Irnparipinnate. 

 Palmate. Bipinnate. 



Tripinnate. 



The Margin of Leaves may be (i) Entire, (2) Serrate, (3) Biserrate, 

 (4) Crenate, (5) Dentate, (6) Ciliated, (7) Spiny. 



The Apex may be (i) Acute, (2) Obtuse, (3) Acuminate. 



The Margin may be divided as (i) Palmatisect, (2) Pinnatifid, 

 (3) Pinnatisect, (4) Palmatifid, (5) Palmate, (6) Lobed. 



Stipules may be leaf-like, or membranous. 



Scale Leaves. These are found to be modified leaves ; they protect 

 the buds from injury. 



Bracteate Leaves. These are found at the base of the flowers, and 

 may form an involucre, cupule, or spathe. 



