Ch. [X.] LEAVES. “ 4§ 
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190. The form of the leaf is expressed by various terms we, 
borrowed from the names of different objects; as digitate, 
(from digitus, the finger,) &c. Kor the explanation of these 
different terms you must consult the vocabulary as often as 
you find those ygu do not understand. We will, however, il- 
lustrate some oflthe most common forms of simple leaves. 
Fig. 27. 
. 191. Orbicular, or the round leaf; the Nasturtion affords an 
example of this kind; (see Fig. 27, a;) this is also peltate, 
having its petiole inserted into the centre of the leaf, and thus 
resembling a shield. 
192. Reniform, (from the Latin ren, the kidney,) or as it is 
sometimes called kidney-form ; the Ground-ivy (Glechoma) 
has a leaf of this kind. (See Fig. 27, b ;) It is crenate, or has 
a margin with scolloped divisions, ciliate, being fringed with 
hairs like eyelashes. 
193. Cord ate, (from the Latin cor, the heart, ) or heart-shaped. 
Fig. 27, (c,) represents a cordate leaf with an accuminated point ; 
that is, acute and turned to one side; the margin is serrated ; 
an example of this kind of leaf may be seen in one species of 
the Star-flower, Aster cordifolium. 
Fig. 28. 
190. What terms express the form of the leaf ? 
191. Describe an orbicular leaf, 
192. What is a reniform leaf ? 
193 What is cordate ? 
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