96 



MORPHOLOGY OF LEAVES. 



term oblanceolate is superfluous. The following terms desig- 

 nate leaves with a notched instc.-id of narrowed base. 



Cordate, or //""/-/-.v/m/W. \vlicn a leaf of an ovate form, or 

 something like it, has the outline of its rounded b :i se tinned in 

 (forming a notch or \/////.v) wliere the stalk is attached, as in 

 Fig. 1 7i>. 151. Also Fig. 149, Pontcderia, a leaf of the parallel- 

 veined class. 



11' a if mi. or Kidney-shaped, ]ike the last, only rounder and 

 broader than long. (Fig. 158.) 



Aurli-iiluh', or Eared, having a pair of small and blunt pro- 

 jections, or ears, at the base, as in Magnolia Fraseri. Fig. 17s. 

 Sayittate, or Arrow-shaped, where such ears are acute and turned 



downwards, while the 

 main body of the blade 

 tapers upwards to a 

 point, as in the com- 

 mon species of Sagit- 

 taria or Arrow-head, 

 and in the Arrow- 

 leaved Polygonum. 

 (Fig. 165, 177.) 



Hastate, or Jlalberd- 

 slntped, when such 

 lobes at the base point, out wards, giving, the leaf the shape of the 

 halberd of the olden time, as in Polygonum arifolium (Fig. 17l>) 

 and Sorrel, Fig. 1G3. 



182. Peltate or Shield-shaped leaves are those in which a blade 

 of rounded or sometimes of other shape is attached to the petiole 

 by some part of the lower surface, instead of the basal margin : 

 those of Water-shield or Ilrasenia, of Nelumbium. and of Ilydro- 

 cotyle umbellata are marked examples. The anomaly is mor- 

 phologically explained b\ a comparison with deeply cordate or 

 remlbrm leaves having a narrow sinus, such as those of Nym- 

 pluca or Water Lily, and by supposing a union of the approxi- 

 mated edges of the sinus. Fig. I.V.I and 1 ('<>, from two species 

 of Ilydrocotyle. one with open and the other with dosed sinus 

 obliterated by the union, illustrate this. 



is: 1 ,. As to llxtn'init.v, whether base or apex, there are several 

 descriptive terms, expressive of the principal modifications; 

 such as 



Acuminate, tapering, either gradually or abruptly, into a 

 narrow more or less prolonged termination. (Fig. 180.) 



179 



FIG. 177-179. Sagittate, auriculate, ami hastate leaves. 



