THE BEGINNINGS OF LIFE. 73 



It is an unstable collocation of Matter, capable of 

 growing by selection and interstitial appropriation of 

 new matter which then assumes similar qualities, of con- 

 tinually varying in composition in response to variations 

 in its Medium, and which is capable of self-multiplication 

 by the separation of portions of its own substance l . 



It is one of the properties of living bodies, one of 

 the consequences of the peculiar collocation of their 

 molecules, that they are only slightly amenable to the 

 influence of some of the physical forces which tend to 

 disintegrate and destroy many forms of not-living 

 matter. It was under the influence of this considera- 

 tion principally, that Bichat was led to define life as 



1 M. Nicolet, in his ' Memoire sur les Amibes k Corps Nu,' speaking 

 of these creatures, which have been subsequently named Protamceba 

 by Professor Haeckel, and which are about the simplest of known 

 living things, says : ' La substance qui en forme le corps peut etre 

 considered comme 1'expression d'un premier degr6 d'animalite de la 

 matiere organique. Ici point d'appareils speciaux affectes aux fonctions 

 de la vie ; point d'organe, meme rudimentaire, indiquant une similitude 

 plutot animale que v^getale ; point de muscles, point de fibres, point de 

 cellules, rien de ce qui manifestent la vie dans ces deux regnes : et ce- 

 pendant elle vit, elle remplit des fonctions qui necessitent des organes par- 

 ticuliers dans tous les autres etres ; elle se meut, elle se nourrit, elle se 

 reproduit, elle digere, mais la locomotion s'opere par la pretension et la 

 retraction alternative ou simultane"es des differentes parties de sa masse. 

 . . . L'Amibe n'a done aucune organisation appreciable; et lorsque, 

 depouille"e des matieres etrangeres qu'elle renferme presque toujours dans 

 sa propre substance, elle glisse sur la surface d'un lame de verre im- 

 mergee, elle se presente toujours comme une gelee vivante, finement 

 granulee, de"pourvue de teguments, et d'un diaphaneite souvent telle, 

 que sa presence ne se manifeste que par un simple difference de re- 

 fraction.' 'Arcana Naturae,' J. Thompson, 1859, p. 23. 



