Il8 THE BEGINNINGS OF LIFE. 



colloids even in a more eminent degree, and to such 

 an extent as to enable them to carry on a continuous: 

 series of molecular changes in response to the inci- 

 dence of mere ordinary physical forces. This, however, 

 is but a further degree of complexity in a direction 

 already indicated. All intermediate degrees of mole- 

 cular mobility may be traced (amongst various crystal- 

 line and colloidal states of matter) between the dis- 

 tantly successive changes from one to another mode of 

 polar equilibrium which is alone possible with the ma- 

 jority of crystals and the continuous changes of living 

 matter l . The lapse from one mode of statical equi- 



1 A very good instance of such an intermediate product is to be found 

 in the remarkable substance called ' myeline,' which, when immersed in 

 water, protrudes delicate tubes that bend in all directions (Montgomery, 

 ' On the Artificial Formation of so-called Cells '). But, as Robin has 

 shown, similar or even more remarkable movements and changes of 

 form (riot due to contractility in its ordinary sense) are to be seen in other 

 fatty extracts derived from dead animal substances. (See ' Mem. de 

 1'Acad. de Medecine,' 1859, p. 248.) This is especially the case with 

 fatty extracts obtained from the blood, when they are mixed with water 

 or albuminous fluids : ' Des amas de ces extraits, on voit aussi sortir et 

 s'allonger sous les yeux de 1'observateur des filaments d'aspect tubuleux, 

 prenant des dispositions rectilignes, coudees, onduleuses ou spiroides, 

 analogues a celles de divers elements anatomiques ; parfois Fextremite 

 de certains de ces tubes se resserre, devient monoliforme, et les reserre- 

 ments vont jusqu'k produire une scission avec separation complete d'un 

 globe creux, comme dans le cas de production des spores a 1'extremite 



des cellules tubuleuses de divers champignons, oidies, etc Lorsque 



ce sont des gouttes spheriques ou a contour sinueux qui se sont formees, 

 on peut les voir sous le microscope non pas s'inflechir dans un sens et 

 dans 1'autre, comme les filaments tubuleux precedents, mais changer de 

 forme incessamment, par suite de resserrements et de dilatations alter- 

 natifs de certaines de leurs parties. Ces resserrements vont meme 





