THE LOWEST FORMS OF LIFE 



for all that breathe or live ; the noblest forms of 

 animal life, all may be traced back to the modifica- 

 tions of these or similar primordial structures. They 

 are disseminated widely throughout all nature. It is 

 difficult to exclude their presence when we wish to. 

 They can be destroyed by heat or by boiling, but, 

 like creatures of a higher order, though we destroy 

 them, we cannot create them. 



The chemical composition of these bodies, or of 

 Protoplasm, is nearly identical, whether in plants or 

 animals, all consisting of albumonoids themselves 

 composed of carbon, hydrogen, nitrogen, oxygen, 

 with small quantities of sulphur and phosphorus. 

 Water constitutes usually over eighty per cent, of 

 their mass. It is very difficult with some of the 

 lowest forms to decide whether they should be viewed 

 as plants or animals. They move from place to 

 place, but are without organs of any kind, many of 

 them being formless, gelatinous masses, whose shape 

 constantly changes by the protrusion of any one por- 

 tion of their mass in one or another direction, for loco- 

 motion, or to absorb through any part of their sub- 

 stance such material as they feed upon. Haeckle 

 places them in a specific class " Monera " as being 

 neither animal nor plant. Of these the Amoeba are 

 placed by other writers in the animal line, principally 

 on account of the nature of their food, but also from 

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