52 NOMENCLATURE OF THE LEAF. 



t. Mealy when the white powder is less minute, or is mealy, as 

 in bird's-eye primrose. 



n. Glaucous when the dust or bloom is of a blneish-green or sea- 

 green colour, as in palma christi, or castor-oil plant. 



v. Viscid when it is covered with a clammy resinous exudation, 

 as in clammy catch-fly. 



w. Glutinous when the exudation is adhesive, but instead of 

 being resinous, it is gummy, or soluble in water, as in clammy prim- 

 rose. 



Rough when they assume an uneven character. The varieties are, 



x. Scabrous when they are thickly covered with small emi 

 nences, which are not visible, but can be felt on running the finger 

 along, as in black knapweed. 



y. Warty when they are studded over with small hard warts, 

 which can be both seen and felt, as in warty spindle-tree. 



z. Vesicular when the roughness depends on a small elevation 

 of the epidermis, comtaining a watery fluid, which gives the plant the 

 appearance as if it was covered with ice, as in the ice-plant. 



NOMENCLATURE OF THE LEAF. 



1. All leaves in the infant bud, are very peculiarly 

 folded up, so as to occupy the smallest possible space. 



This regulates the expansion of the leaves, when the bud opens in 

 the spring ; the manner of which, is always the same in individual 

 plants of the same species. 



2. The expanding of leaves from the bud, is techni- 

 cally denominated foliation; and the figures which they 

 assume at the time, may be conveniently included under 

 the terms, folded, overlapping, and rolled. 



The best method of ascertaining the character of a bud, as respects 

 its foliation, is to cut it across while it is opening, and then examine 

 the sections of the leaves. 



3. Folded : -This kind of foliation displays the leaf, 



