6 BOTANY. 



masses in tUe large vacuole ; these again may produce vacuoles within 

 themselves, and thus give rise to a peculiar and at first sight perplex- 

 ing structure (Fig. 4). 



6.-The most remarkable peculiarity of living protoplasm is 

 its physical activity. When the proper conditions are pres- 

 ent, a living mass of protoplasm is apparently never at rest, 



but, on the contrary, 

 continually altering its 

 shape and changing the 

 position of its constit- 

 uent parts. The move- 

 ments are all of the 

 same general nature ; 

 each one maybe regard- 

 ed as the aggregate re- 

 sult of the chemical and 

 physical changes taking 

 place in the substance 

 of the protoplasm. 



We may study the ac- 

 tivity of protoplasm 

 under two conditions, 

 which will give us the 

 two cases. (1.) The 

 Activity of Naked Pro- 

 Fig. 4.— Form* of the protoplasm contained in toplasm, and (2.) The 

 cells. A and B. of Indian Com (Zea mait) ; A, . „/ ;„;i„ „j! "n,.„i„„1nr,«, 

 cells from the first leal-shcaf'i of a germinating Activity 01 1 lOtopiasm 

 plant, showing the froihy condition of the proto- p,,„i„„„^ ™ „ npll.-wall 

 the many vacuoles separated by thin e'H^lObLU m d, <^uu Wd.li. 



7.— The Activity of 



plasm, ^ _.^_ . 



plates. B, cells from the first internode of the 



germinating pi -nt ; the protoplasm is broken up 



into many rounded miisf'es, in each of which there 3S'aked. Frotoplasm. 



is a vacuole, b ; these are the so-called " sap-vesi- _^. _ 



cles." C, a cell from the tnber of the Jerusalem ihe lOW Organisms 



Artichoke (Heiiarithus ii^berosifs) after the aciionof ■• ,i -,«- 



iodine and dilute sulphuric acid ; A, cell-wall ; i, knOWn aS the Myxomy- 



cetes, or Slime Moulds, 



nucleus ; p^ contracted protoplaflin.— After Sachs. 



present the best examples of the activity of naked vegetable 

 protoplasm. In their plasmodia (as the masses of naked proto- 

 plasm are called), many kinds of movements may be observed, 

 the commonest of which is streaming. In plasmodia com- 

 posed of thin (i.e., watery) protoplasm, streams or currents 

 of the latter may be seen running in yarious direotions 



