n] 



STIPULATE LEAVES 



21 



Rhamnus Frangula Robinia 



Laburnum 

 Cherry 

 Blackberry 

 Salix pentandra 

 S. cinerea 

 Birch 



Prunus Pad us 

 Primus Avium 

 Viburnum Opidus 

 S. Caprea 

 Ha,zel 

 Alder. 



Sarothamnus 

 Blackthorn 



Roses 



Salix triandra 

 8. aurita 

 Hornbeam 



The following have deciduous or caducous stipules, 

 i.e. they fall at once on or soon after the emergence of 

 the leaf from the bud : 



and many other Willows. 



If the student collects a number of common simple 

 leaves, noticing at the time that he is taking average 

 specimens of the foliage, he soon becomes convinced that 

 there is some relative stability of form, and that a type- 

 shape can be chosen for each kind from which the rest 

 of the foliage does not usually depart very much. Absolute 

 geometrical constancy he will not find, and some plants 

 show far more variety than others ; but in cases like the 

 following, most of the leaves on the plant or tree will be 

 found fairly exemplified by any normal specimen. 



Suppose we take average leaves of Scotch Pine, Yew, 

 Hypericum, Beech, and common garden Nasturtium 

 {Tropceolum), we shall find that they conform most nearly 

 to the following geometrical outlines, termed acictdar, 

 linear, oblong, oval (or elliptical), and sub-rotund in order 



