THE BEGINNINGS OF LIFE. 423 



^ I am convinced it will be at some future day shown 

 that all the green, and some of the red colored forms 

 similar to Euglena, and which have had several names 

 bestowed upon them, are but transition states of fresh- 

 water or marine Confervoid Algae.' 



But seeing that metamorphic changes of the most 

 surprising nature occur in individual masses of algoid 

 protoplasm, would it not be reasonable to suppose that 

 Astasise or Euglenae may also, at different times, 

 undergo a number of heterogenetic changes, leading to 

 the production of totally different forms, both animal 

 and vegetal. And, as a matter of fact, such phenomena 

 were long ago stated to occur. The accurate obser- 

 vations of Dr. Gros, which we shall have to quote in 

 the next chapter, do of themselves fully suffice to show 

 that such organisms easily pass, at different times or 

 under different conditions, into the most diverse 

 representatives now of the Animal and now of the 

 Vegetal Kingdoms. 



Although we may be astounded by the changes re- 

 corded in this chapter — at the very high forms, and at 

 the diversity of the living things which are evolved, 

 as compared with those which arise in the pellicle on 

 organic infusions— it may also be seen that these dif- 

 ferences do not remain wholly unaccountable. Whether 

 we have to do with one of the lower aquatic animals, 

 with an Alga, or with any other submerged cryptogam, 

 actual portions of its living matter, as such, undergo 



