CONCERNING PROTOPLASM. 69 



of plants. Their protoplasm is as highly contractile under stimulus 

 as is that of the animal. Conceive of a vegetable cell being rup- 

 tured as, indeed, takes place in certain phases of lower plant-life 

 and we should find escaping therefrom protoplasm as active as that 

 of our Amoeba, and which, indeed, would comport itself in an exactly 

 similar fashion to that animalcule. Consider, for instance, what takes 

 place in the multiplication of the lower plant-life that forms " the 

 green mantle of the stagnant pool." Here, in due season, the proto- 

 plasm, found in the interior of the cells of which these green Conferva 

 of the stagnant pool are composed, will break up into minute parti- 

 cles, which are duly discharged from custody by the rupture of the 

 cell-wall that formerly imprisoned them. These minute bodies, thus 

 liberated, are named " zoospores." They flit about in the water, and 

 exhibit as free and active an existence as the animalcules which 

 disport themselves side by side with these plant-germs; and they like- 

 wise exhibit an identity of protoplasmic composition with the lower 

 animals that people the stagnant depths. After a period spent in this 

 active existence, the zoospores settle down and grow each into a new 

 plant resembling that from which it sprang. Or, mayhap, meeting with 

 a fellow-spore, a more intricate relationship may be induced ; a third 

 and new body may be produced as the result of this contact ; and 

 from this new body foreshadowing the "seed" of the higher plant 

 the adult Conferva will in due time grow. Thus we find that, in 

 addition to the resemblance between the protoplasm of the animal 

 and that of the plant in respect of appearance and composition, there 

 exists a closer likeness still in the common movements which proto- 

 plasm, whether derived from the animal or the vegetable, exhibits. 



It is not necessary that we should dwell upon other examples of 

 the marked irritability of protoplasm in lower plant-life to demon- 

 strate the community of phenomena which this substance is every- 

 where seen to exhibit in its simple and primitive condition. The 

 life-history of the commonest seaweed that fringes the rocks, would 

 show phenomena of similar kind, and would convince us that power 

 of motion, by common consent the exclusive right and property of the 

 animal, is rather to be viewed as a quality of the protoplasm which 

 forms the living parts of both series of organisms. For, like many of 

 its lower neighbours, the seaweed begins its existence as a minute 

 speck of protoplasm that possesses from nature a roving commission, 

 and swims about freely in its native waters by means of cilia, or fila- 

 ments, resembling those by which the animalcules propel themselves. 

 Ultimately this roving life is abandoned for the stay-at-home exist- 

 ence of the mature seaweed, which in due course arises by cell- 

 growth and protoplasmic multiplication from the once active "spore." 

 Whether studied in the lower animal or in the plant, protoplasm 

 is thus seen to possess essentially the same qualities and properties 



