114 WOODY PLANTS OF MASSACHUSETTS. 



hemisphere. A few are found upon the mountains within the 

 tropics, but are unknown in the valleys. 



It was formerly considered a part of the much larger family 

 of Amentaceae. As now constituted, it is a strictly natural 

 family. The trees which belong to it are remarkable for their 

 thick and rugged bark, and for the great abundance of the prin- 

 ciple of tannin which it contains. They have large and strong 

 roots, penetrating very deep, or extending very far, horizontally, 

 beneath the surface, and sometimes, as in the case of the oak, 

 both. The trunks are distinguished for their massiveness, and 

 for the weight, strength, and, in most cases, the durability of 

 their wood, and its preeminent importance in the arts. Their 

 branches are long and irregular, and form a broad head of 

 greater depth than belongs to the trees of any other family. 



The buds are fitted for a climate with severe winters, the 

 plaited or folded leaves being covered by imbricate, external 

 scales, and, often, still further protected by a separate, downy 

 scale, surrounding each separate leaf. The leaves are plane, 

 and alternate, and usually supported by a footstalk, at the base 

 of which are two slender leaflets or stipules, which, for the most 

 part, fall off, as the leaf expands. 



The fruit is valuable as food to man and the animals depend- 

 ant on him. The fruits of the chestnut and hazel have been 

 long cultivated on the Eastern continent, and much improved 

 in size and quality. All are doubtless susceptible of it ; but the 

 life of these trees is so long, in comparison with the duration of 

 man, that experiments for this purpose must be carried on by 

 successive generations. 



This family includes trees and shrubs whose male and female 

 flowers are separate, but on the same trunk. The male flow- 

 ers, which appear early in the spring, are in long tassels called 

 aments or catkins, made up of a great number of separate, cup- 

 shaped, jagged scales or membranous leaves, to the base or side 

 of which, beneath or within, are attached the stamens, from 

 five to twenty in number. The female flowers are usually 

 bud-shaped. The ovaries or seed-vessels are seated within a 

 leathery cup or involucre, are surrounded by an irregularly 

 toothed calyx, and tipped with several stigmas. They contain 



