BOTANY FOR BEGINNERS 



CHAP. 



FIG. 42. Diagram 

 illustrating f 

 phyllotaxis. 



FIG. 43. Diagram 

 illustrating ^ 

 phyllotaxis. 



simple when the blade consists 

 Elm, Holly, and Dead- 

 nettle. The blade may 

 be divided, but, unless it 

 is cut down to the mid- 

 rib, it is still a simple 

 leaf. Compound leaves 

 are cut into a number of 

 distinct pieces, as in the 

 Pea and the Ash. Each 

 separate part of such a 

 leaf is called a leaflet. 



Simple Leaves. 

 Leaves vary much in 

 shape or general outline. FIG. 



EXPT. 28. Collect and ex- 

 amine branches of the Oak, 

 Wallflower, Deadnettle, Bed- 

 straw, and Elm. Determine 

 their phyllotaxis, and mark on 

 the stem the leaf-cycle or the 

 cycle made in passing from one 

 leaf to the leaf vertically above. 

 This can be done with a piece 

 of coloured chalk, and if the 

 leaves are also numbered the 

 arrangement will be seen at a 

 glance. 



Different Kinds of 

 Foliage Leaves. When 

 the leaves spring from an 

 underground stem, as in the 

 Daisy and Dandelion, they 

 are called radical leaves. 

 If^ they grow on an aerial 

 stem, as the leaves of the 

 Oak and Wallflower, they 

 are spoken of as cauline 

 leaves. 



Foliage leaves may be 

 either simple or com- 

 pound. Leaves are called 

 of a single piece, as in the 



44. Radical leaves of the Primrose. 



