A PLAN FOR LEAF IDENTIFICATION. 



All leaves may be divided into five general classes, as follows: 



I. Simple alternate-growing leaves. 

 II. Simple opposite-growing leaves. 



III. Compound alternate-growing leaves. 



IV. Compound opposite-growing leaves. 

 V. Evergreen leaves, of the Pine family. 



The first four classes which comprise the deciduous leaves are sub- 

 divided into two classes, as follows : 



1. Without teeth. 



2. With teeth. 



These two classes are again subdivided, as follows: 



A. Edge not divided or cut into. 



B. Edge divided or cut into. 



Class V is subdivided as follows : 



1. With long needles. 



2. With short, flat, blunt needles, or with soft needles. 



3. With short, sharp needles, or with scales. 



Under this general classification the leaves are arranged in botanical 

 succession through the following chapters : 



I. Simple alternate leaves : 



Edge not divided. 

 Edge divided. 

 Edge not divided. 

 Edge divided. 



1. Without teeth, j 



2. With teeth. 



A. 

 B. 



Chap. II. 

 Chap. III. 

 Chaps. IV to IX. 

 Chaps. X to XIII. 



II. Simple opposite leaves : 



1. Without teeth. 



2. With teeth. 



Edge not divided. 

 Edge not divided. 

 Edge divided. 



III. Compound alternate leaves : 



A. 



Ik 



1. Without teeth, 



2. With teeth. 



( Leaflets bordering main 

 j leaf stem. 



j Leaflets bordering main 

 ( leaf stem. 



IV. Compound opposite leaves : 



1. Without and j Leaflets bordering main 



with teeth. ( leaf stem. 



2. With teeth. Leaflets radiating. 



V. Evergreen leaves, of the Fine family : 



1. With long needles. 



2. With short, flat, blunt needles, or with 



soft needles. 



3. With short, sharp needles, or with scales. 



Chap. XIV. 

 Chap. XV. 

 Chap. XVI. 



Chap. XVII. 

 Chap. XVIII. 



Chap. XIX. 

 Chap. XX. 



Chap. XXI. 



Chap. XXII. 

 Chap. XXIII. 



xiv 



