BIOPLASM OR LIVING MATTER. 37 



living plasm , germinal or growing matter. Now 

 in the drawing, masses of bioplasm or bioplasts 

 will be seen embedded in, or in intimate relation 

 with, the different tissues. In connection with 

 the muscular tissue of the heart are very 

 numerous elongated oval bioplasts, situated at 

 short intervals from one another. More than 

 five times as many of these exist in the cardiac 

 muscular tissue as in ordinary muscular fibre. 

 The activity of the changes of the muscular 

 tissue of the heart is very great. It is always 

 acting, and consequently new tissue is con- 

 tinually being formed to take the place of that 

 which wears away. , This is why the bioplasts 

 are so abundant in the particular specimen of 

 muscular tissue which I have selected for illus- 

 trating these remarks concerning the impor- 

 tance of bioplasm. 



At an early period of development, the heart 

 was represented by a collection of spherical 

 bioplasts situated close to one another. These 

 divided and sub-divided until a considerable 

 mass had been formed. Some bioplasts were 

 concerned in the formation of muscle, others 

 were to produce nerve, and from others connec- 

 tive tissue only was to be developed. But at this 



