THE CELL DOCTRINE. 55 



j. HUGHES' BENNETT, 1855.* 



Dr. Bennett, of Edinburgh, considers that "the 

 ultimate parts of organization are not cells nor 

 nuclei, but the minute molecules from which these 

 are formed. They possess independent physical and 

 vital properties, which enable them to unite and 

 arrange themselves so as to produce higher forms. 

 Among these are nuclei, cells, fibres, and membranes, 

 all of which may be produced directly from mole- 

 cules. The development and growth of organic 

 tissues is owing to the successive formation of his- 

 togenetic and histolytic molecules. The breaking 

 down of one substance is often the necessary step to 

 the formation of another; so that the histolytic or 

 disintegrative molecules of one period become the 

 histogenetic or formative molecules of another." 



Again : " As to development, the molecular is the 

 basis of all the tissues. The first step in the process 

 of organic formation is the production of an organic 

 fluid ; the second, th,e precipitation in it of organic 

 molecules, from which, according to the molecular 

 law of growth, all other textures are derived either 

 directly or indirectly. "f 



* Bennett's Practice of Medicine. Am. Ed. of Wm. Wood & 

 Co., N.Y.: 1866, p. 118. 



Prof. Bennett has further elaborated his views in the Edinburgh 

 Medical Journal, March, 1868, and The Popular Science Keview, 

 January, 1869, but his conclusions are substantially the same as 

 quoted. 



t Op. citat., p. 119. 



