FORMS OF SIMPLE LEAVES. 



35 



Fig. 19. 



OBTUSE. 



Fig. 20. 



OBCORDATE, 



Fig. 21. 



EMARGINATE. 



An a'cerose leaf (from the Latin, acer, a needle), 

 in the form of a needle, is seen on pines ; it is linear 

 acuminate. 



An obtuse leaf folium obtusum (fig- 19), blunt 

 pointed ; the apex is broader than the base, and forms 

 the segment of a circle. The primrose has a leaf of 

 this kind. 



An obcordate leaf folium obcordatum (fig. 20). 

 The Latin word ob is prefixed to technical terms, 

 to indicate that a thing is inverted : obcordate means 

 inversely cordate (see fig. 51), the notch being at 

 the apex instead of the base of the leaf. Example : 

 the Oxalis acetosella, sheep-sorrel. 



An ema'rginate leaf folium ema.rgina.tum (fig. 

 21). Emarginate (from the Latin, e, from, and 

 margo, margin, or edge), notched. Having a notch 

 at the end. Example : the Geranium emarginatum. 



When the notch or sinus is very obtuse, it is said 

 to be retuse, or almost emarginate. 



A. lanceolate leaf 

 folium lanceolatum (fig- 

 22) lance-shaped, as in 



the olive. Narrowly ob- Fig. 22. LANCEOLATE. 



long and tapering to each 

 end. The peach tree has leaves of this description. 



An acute leaf folium 

 acutum (fig. 23). Sharp 

 pointed. Terminating in 

 an acute point without Fig-. 23. ACUTE. 



tapering suddenly. The Solidago odora, an aromatic plant, is 

 an instance. 



A seta'ceo-acuminate leaf 

 folium setaceo-acumina- 

 tum (fig. 24). (From the Fig. 24. SETACEO-ACUMINATE. 



Latin, seta, a bristle.) The point of the leaf terminated by a 

 straight bristle-like projection. The Quercus phellos, willow- 

 leaved oak, is an example. Leaves are 



Mucronatc (from the Latin, mucro, in the genitive, mucronis, 

 a sharp point), when an obtuse leaf terminates in a short, rigid 

 point, formed by the projection of the midrib. 



Cuspidate (from the Latin, cuspis, the point of a spear or 

 other weapon), when it is more gradually prolonged into a rigid 

 point. 



Pungent, when it terminates in a hard sharp point, like the 

 leaves of thistles. 



