THE FORMS OF LEA VES 



121 



anists define lanceolate to be]; 7, linear; 8, subulate [awl-like]; 

 9, reniform; 10, cordate; 11, luuulate [or crescent-shaped]; 12, tri- 

 angular; 13, sagittate; 14, cordate- sagittate; 15, hastate; 16, cleft 

 ["fissum," now called obcordate] ; 17, three-lobed, or trilobate; 18, 

 premorse [irregularly notched at the end]; 19, lobed, or lobate; 20, 

 five-angled; 21, erose [jagged or bitten]; 22, palmate; 23, pinnati- 



fid; 24, laciniate; 25, sinuate; 26, 

 dentate-sinuate; 27, retrorse- sinu- 

 ate; 28, parted; 29, repand; 30, 

 dentate; 31, serrate; 32, doubly- 



FiG. 118. 

 Variation in birch leaves. 



serrate; 33, doubly - crenate ; 34, cartilaginous; 35, acutely -erenate; 

 36, obtusely- crenate; 37, plicate; 38, erenate; 39, crisped; 40, ob- 

 tuse; 41, acute; 42, acuminate; 43, obtusely - acuminate ; 44, emar- 

 ginate acute. 



Suggestions. — We have said (127) that the forms of leaves are 

 described by comparing them with purely arbitrary measures. We 

 should not expect them always to match these measures ; in illus- 

 tration of which, let the pupil cut the form of any leaf in paper. 



