530 CONSERVATIVE ORGANS. [LECT. X. 



the leaf forms a curve, the convexity of which 

 (e.) is upwards; inflex (incurva seu inflexa), 

 when the convexity is downwards (/!); and 

 pendulous (dependens, pendula, seu demissa), 

 when the whole leaf droops (g. g.). When the 

 leaf is so twisted that one part of it is vertical 

 and' another horizontal, it is termed twisted 

 (oUiquum, deviatum), as exemplified in oblique- 

 leaved Garlic, Allium obliquum; and reversed 

 (resupinatum) , when the surface which is com- 

 monly undermost *is found uppermost, as in 

 spotted-flowered Alstraemeria, Alstrseineria pele- 

 grina. If $1 the leaves lean or point to the 

 same side, as in Polygonatum mitltiftora (see 

 fig. c. p. 246), the direction is termed unilateral 

 (secunda seu unilateralis) . Some leaves, instead 

 of being 1 suspended in the air, lie on the surface of 

 the ground, as for instance in several species of 

 the genus Plantago, and the common Daisy, 

 Bellis perennis ; in which case the direction is 

 termed procumbent (procumbens seu humifusaj. 



In aquatic plants, the direction of the leaves is 

 determined by their relation to the surface of the 

 water. When the leaf is raised upon its pe- 

 tiole, above that surface, and is, therefore, an 

 aerial leaf although growing in water, it is said 

 to be emerging (emersa), as exemplified in the 

 greater Water Plantain, Alisma Plantago: if 

 it lie on the surface of the water, and the up- 



