FOLIAGE-LEAVES. 121 



the leaf is glabrous ; if present, the degree of hairiness is 

 described by an appropriate adverb ; if the leaf is com- 

 pletely covered, it is villous or villose ; and if the hairs are 

 on the margin only, as in our Clintonia, it is ciliate. 

 Some leaves, like those of the Cabbage, have a kind of 

 bloom on the surface, which may be rubbed off with the 

 fingers ; this condition is described as glaucous. 



183. A few plants have anomalous leaves. Those 

 of the Onion are filiform. The Pitcher-Plant of our 

 northern swamps has very curious leaves (Fig. 169), 

 apparently formed by the turning in and cohesion of the 

 outer edges of an ordinary leaf so as to form a tube, 

 closed except at the top, and armed on the inner surface 

 with bristles pointing towards the base of the leaf. 



184. Finally, as leaves present an almost infinite 

 variety in their forms, it will often be necessary in 

 describing them to combine the terms explained above. 

 For instance, a leaf may not be exactly linear, nor exactly 

 lance-shaped, but may approximate to both forms. In 

 such a case the leaf is described as lance-linear, and so 

 with other forms. 



The following form of schedule may be used with 

 advantage in writing out descriptions of leaves. Two 

 leaves one of Maple and one of Sweet Brier are 

 described by way of illustration. If a leaf is compound, 

 the particulars as to outline, margin, apex, base, and surface 

 will have reference to the leaflets. 



The exercise-book prepared to accompany this work 

 contains a supply of blank schedules for leaf-description, 

 with space for drawings. 



