132 PLANT LIFE. 



spray of foliage, or the leaves of the whole plant form a 

 nearly perfect light screen. It is in this necessity for 

 fitting closely together so as not to lose any of the sun- 

 shine, that we find an explanation for the varied and 

 beautiful shapes of leaves. The idea, namely, that of 

 covering a blank space without crowding, is essentially 

 the same as underlies all decorative art of the nature, for 

 instance, of wall-papers. Hence leaf-shapes, as a rule 

 very imperfectly understood, form the groundwork of 

 most art work of that kind. 



The outline of the leaf is, in a general way, governed 

 by this mosaic necessity ; but the details of its shape are 

 affected by the balance of the leaf on its stalk, as well 

 as by the necessity that it shall move freely in the 

 wind, and by other considerations. 



The following are amongst the important shapes of 

 leaves : 



(i) Leaves broadest near the base or stalk, such as 

 ovate (egg-shaped), lanceolate (lance-head-shaped), cordate 

 (heart-shaped). 



(2) Leaves as broad in the middle as anywhere else, such 

 as linear (long and narrow), oblong (brick-shaped and 

 rounded at the edges), circular, etc. 



(3) Leaves broadest near the tip, such as obovate^ oblan- 

 ceolate, obcordate, which are similar to those of the first 

 group in outline, but the stalk is attached at the narrow 

 end instead of at the broad. These forms include also 

 the spathulate or daisy leaf 



The examples which follow are chiefly from very 

 common plants. Wherever they are intelligently looked 

 for many others will be found. 



The Daisy has a very dense and close circle of leaves, 

 forming a little rosette or tuft, which is flat and pressed 

 close to the ground. The leaves, therefore, cover and 



