HOW PLANTS MARRY. 



75 



just parallel to one another, with their cells facing 

 (Fig. 14). Then each opposite pair of cells begins 

 to bulge a little at the point where they nearly 

 touch (a and b in the figure), till at last they join 

 and coalesce with one another (c and d in the fig- 

 ure). The contents of one cell pass into another 

 (at e), and the two form a sort of egg (/), which 

 lies quiet for a while, and then buds out into a 

 new thread or hair-like plant by division. In this 

 strange process we have the beginning of sex 

 the first hint of plant and animal marriages. 



What is the meaning and good of it ? Why do 

 the plants act thus? That question we don't yet 

 quite understand, perhaps; but this seems to be 

 in part at least its reason. Proto- 

 plasm requires to be kept, as it 

 were, perpetually young and ever 

 fresh; it cannot afford to lose its 

 elasticity and its plasticity. If it 

 does, it grows old in time and dies. 

 To prevent this misfortune, and 

 the death of all things, plants and 

 animals have invented all sorts of 

 curious expedients; for example, 

 the protoplasm of a living cell 

 sometimes breaks out of the cell- 

 wall, and undergoes a process which 

 is called " rejuvenescence," or grow- 

 ing young again. It lies quiet for 

 awhile in its free condition, and 

 then begins to build up a new wall 

 afresh for itself. It seems by the process of 

 breaking out to have gained for itself a new lease 

 of life, as we ourselves often do by a trip abroad 

 or change of sea and air and occupation. How- 

 ever this may be, it is certain at least that the 



\ 



FIG. 14. Begin- 

 nings of sex in 

 a pond weed, 

 very much mag- 

 nified. 



