XXil INTRODUCTION TO BOTANY. 
The epidermis, or surface, is said to be, 
strigose, when short, stiff hairs lie close-pressed to the surface, and 
all in one direction ; strigil/ose, when such hairs are very short 
or small. 
tomentose or cottony, when the hairs are soft, short, dense, somewhat 
interwoven, and usually white or whitish. 
woolly, when the hairs are loosely intricate and long, like wool. 
mealy or farinose, when the hairs are very minute, intricate, and 
white, and come off readily, having the appearance of meal or 
dust. 
canescent, canous, or hoary, when-the hairs are minute, close-pressed, 
and white, and not readily to be distinguished separately by 
the eye, but giving a general whitish hue to the epidermis. 
glaucous or glaucescent, when of more or less a pale bluish-green, often 
covered with a bloom like that on a plum or cabbage-leaf. 
148. Hairs are often branched. If forked from the base, the forks 
spreading in opposite directions, the hairs are said to be attached by the 
centre. If several branches radiate horizontally, the hairs are stellate, or 
star-like. Stellate hairs become stellate scales when the rays are confluent 
at base; and the surface is said to be scaly or lepidote. 
149. The term gland is given to several different productions, and 
principally to the four following :— 
1. Small, wart-like or shield-shaped bodies, either sessile or some- 
times stalked, of cellular or somewhat fleshy consistence, occa- 
sionally secreting a small quantity of oily or resinous matter, but 
more frequently dry. They are generally few in number, often 
definite in their position and form, and occur chiefly on the 
petiole or principal veins of leaves, on the branches of in- 
florescences, or on the stalks or principal veins of bracts, sepals, 
and petals. 
2. Minute raised dots, usually black, red, or dark-coloured, of a 
resinous or oily nature, always superficial and apparently 
exudations from the epidermis. They are often very numerous 
on leaves, bracts, sepals, and green branches, and occur even on 
petals and stamens, more rarely on pistils. When raised on 
slender stalks they are called pedicellate glands, or glandular 
hairs, according to the thickness of the stalk. 
3. Small, globular, oblong, or linear vesicles filled with oil, im- 
bedded in the substance of leaves, bracts, floral organs, or 
fruits. They are often very numerous, like transparent dots; 
sometimes few and determinate in form and position. In the 
pericarp of Umbellifere they are remarkably regular and con- 
spicuous, and take the name of vitte. 
4. Lobes of the disk, or other small, fleshy excrescences within the 
flower, whether from the receptacle, calyx, corolla, stamens, or 
pistils. 
II. Anatomy AND PuysioLoey. 
(Abridged from the writings of Professor Lindley and Professor Asa Gray.) 
150. Vegetable Anatomy, or the study of the microscopical structure of 
the compound organs of plants, and Vegetable Physiology, or the study of 
the functions which each organ performs during life, are distinct and 
extensive branches of botany, with which the merely systematic botanist, 
