THE FOBMS OF LEAVES 119 



shaped (as in Fig. 116, which is a cordate-ovate 

 leaf) ; rentform, or kidney- shaped ; anriculate, or 

 eared ; sagittate, or arrow-shaped ; abrupt, or sud- 

 denly narrowed to the petiole (as in the broader 

 leaves in Fig. 114) ; gradually narrowed (as in 

 Figs. 97, 99). The cavity or recess in the base 

 of a leaf, like the grape or moonseed, (Figs. 80, 

 81, 111) is a sinus. 



133. The features of the margins of leaves, 

 like their forms, are interesting because they are 

 intimately related to the origin or • evolution of the 

 particular leaf (and, therefore, of the plant), and 

 also as a means of affording descriptive char- 

 acters. The simple straight margin is said to be 

 entire (Figs. 85, 102, 113, 114). Departures from 

 this form are the serrate, or saw-toothed (Fig. 91) ; 

 dentate, or toothed (Figs. 79, 80, 115, the last 

 being, perhaps, intermediate between serrate and 

 dentate) ; crenate, or scalloped (Fig. 116) ; repand, 

 or wavy, or undulate (Fig. 112 is obscurely so) ; 

 sinuate, which is a deep undulation ; and then 

 follow the deep margins, as cut, jagged, lobed, 

 cleft, and the like, to which we have already 

 given attention (104c) . 



133(1. The diagrams of forms and margins of leaves given by 

 Linneeus are reproduced in exact form and size in Fig. 117: 1, 

 orbiculate; 2, sub-orbioulate (or subrotundate) ; 3, ovate; 4, oval, 

 or elliptical; 5, oblong; 6, lanceolate [narrower than present bot- 



