74 MASSACHUSETTS AGRICULTURE. 



passes on to the leaf, and especially in the leaf, the pure water 

 finds means of escape and the remaining solution is concen- 

 trated and the dissolved earthy matter is deposited. 



These cells multiply with great rapidity. In the mushroom, 

 millions are formed in a single night, multitudes coming into 

 existence in a second of time. In trees, a thick layer is formed 

 each year between the wood and the bark, at first soft and filled 

 with water, at length harder and containing earthy matter. 

 The woody fibres always grow downwards, from the bud and 

 the leaf among the other cells, and crowding them outward 

 causes the stem to expand in diameter. Thus jow have seen 

 the branch or stem when bound by tendrils of the grape or by 

 the bitter-sweet, (^selastnis secandetis) expand above and grow 

 over the ligature while it remained small below. In grafting, 

 too, the woody fibres from the scion shoot down among the cells 

 of the stock, and it grows on. But the bud or scion maintains 

 its orighial character as distinct and perfect as if it had a root 

 of its own, for in the multiplication of cells, each cell produces 

 its like. The product of a bark cell is a bark cell, the product 

 of woody fibre is woody fibre ; the cells that secrete matter 

 peculiar to the sweet apple never secrete matter peculiar to the 

 sour. It is to the cell that we look for the integrity of species, 

 and in it the unknown changes take place that produce varieties. 

 The cell is the laboratory in which the whole character of the 

 plant is wrought out. It is the seat of that invisible, immaterial 

 something we call life. It is the primary element in all 

 organic bodies. We can observe its phenomena, talk of the 

 changes produced in its contents, but of the power that brings 

 it into existence and superintends its wonderful operations we 

 see, we know nothing. 



How beautiful is the foliage of plants, the verdure of 

 nature ; the woody hills with their light green oaks and chest- 

 nut, and darker pines and hemlocks ; the agitated aspen, the 

 meads changing shade with the season, the crops of corn and 

 oats, and rye, varying the landscape like a work of tapestry, the 

 sombre screen thrown over our cottages in the summer noon ; 

 all these are grateful to our feelings. But while the leaf comes 

 into the larger plan of human happiness, it is absolutely essen- 

 tial in the smaller sphere of the existence of the vegetable 

 individual. One great function of the leaf is evaporation and 



