THE CELL DOCTRINE. 77 



by the highest powers, structureless, being visible only 

 through its difference in refracting power as com- 

 pared with the menstruum in which it floats, or by 

 the granular matter it may entangle; and these 

 characters are the same at every period of its exist- 

 ence. They may be studied in the simplest vegetables, 

 in the thallus of the sugar fungus, among the lowest 

 animals, in the amoeba (Plate, Fig. 16), and in higher 

 animals in the mucous, pus, or white blood corpus- 

 cles (Plate, Fig. 10), all of which are composed almost 

 purely of germinal matter ; the very thin periphery 

 of formed material being scarcely appreciable or dis- 

 tinguishable from the diffraction band. 



In its endowments and properties, germinal matter 

 is acting, living, growing, and moving, through some 

 inherent power of its own. It alone, as stated, is 

 capable of producing material like itself out of pab- 

 ulum, and multiplying by division, or a dropping oft 

 of a portion of itself, which portion immediately 

 assumes an independent existence, and grows, main- 

 tains, and reproduces itself like the parent germinal 

 matter. It is also capable of being stained by an 

 ammoniacal solution of carmine, and the younger it 

 is, or more recently formed, the deeper is the stain it 

 assumes. And since the latest formed always ap- 

 pears in the centre of the mass, successive tints, or 

 zones of color, will often be produced in the staining 

 process, growing deeper from without inward, as 

 seen in Fig. 17 of Plate. 



It has been stated that what is called nucleus by 

 Virchow and others, is included in germinal matter. 

 This is true, though the nucleus is not always the 



7* 



