178 THE POPULAR SCIENCE MONTHLY. 



unitary state, the members of which have entirely lost their inde- 

 pendence, and in which a single will rules the whole ; while we may 

 represent the plant as a freely organized federal state, the members of 

 which, in spite of their resignation to the whole body, have yet pre- 

 served a certain degree of independence and self -administration. 



In the federal state of the plant the limbs and boughs correspond 

 to the provinces, the leaves to the villages ; but the village is not the 

 last member of the chain : it is itself a union of citizens, each one of 

 whom, though a member of the state and the village, is an independent 

 being who lives first for himself, and has his own household, all of 

 whose efforts are first directed to the maintenance of his own exist- 

 ence. But while with a just egoism the citizen knows his own good 

 as his immediate object, he thereby participates directly in the ad- 

 vancement of the state organism and contributes to the support of 

 the whole state. Every citizen goes through his independent devel- 

 opment from birth to death ; but the village does not die with the 

 death of the individual, for in his stead come his children to fill the 

 vacant place ; and the village and state are renewed in the unbroken 

 succession of generations. 



It is the same in the plant-state. If we compare the leaf with the 

 village, it also consists of a larger or smaller number of individuals 

 which may be regarded as independent organisms. The citizens, 

 through the union of whom the plant-state is formed, are called by 

 the botanist plant-cells. All plants, without exception, are composed 

 in all their parts of cells, just as every building, from the palace to the 

 hut, consists of building-stones or timbers. Every plant-cell pursues 

 an individual life. Its first effort is only to maintain and develop 

 itself ; it takes its own nourishment and assimilates it, and finally 

 dies, after having, as a rule, first left a posterity in its place. As the 

 cells unite to form cell-villages in the leaves, these unite again to form 

 the provinces of the foliage-boughs, and enter into an interchange of 

 life with each other, and so they maintain the life of the whole plant in 

 the same manner as the collective state-life comes into being through 

 the interworking of the lives of the individual citizens. What we see 

 going on in the life of the plant in the germ and shoot, in flower and 

 fruit-bearing, are only head and state actions in the development of 

 the cell-state and its citizens. 



Our eyes can not perceive these citizens of the cell-state. It is not 

 strange, then, that their existence escaped the knowledge of naturalists 

 till about two hundred years ago. They would still be concealed, and 

 the key to the comprehension of plant-life would be withheld from us, 

 had it not been for the microscope. 



We owe it to the microscope that, where the naked eye perceives 

 only uniform masses, we can now distinguish a wonderful diversity 

 of beautiful tissues ; and that where a rigid stillness seemed to prevail, 

 a fullness of life-processes quite incomprehensible to us is concealed. 



