PROTOPLASM. 27 



able from albumen. As it exists in a living tissue or organ, it 

 differs essentially from mere albumen in the fact of its possess- 

 ing the power of growth, development, and the like ; but in 

 chemical composition it is identical with it. 



This albuminous substance has received various names ac- 

 cording to the structures in which it has been found, and the 

 theory of its nature and uses which may have presented itself 

 most strongly to the minds of its observers. In the bodies of 

 the lowest animals, as the Rhizopoda or Gregarinida, of which 

 it forms the greater portion, it has been called "sarcode," from 

 its chemical resemblance to the flesh of the higher animals. 

 When discovered in vegetable cells, and supposed to be the 

 prime agent in their construction, it was termed "protoplasm." 

 As the presumed formative matter in animal tissues it was 

 called " blastema ;" and, with the belief that wherever found, 

 it alone of all matters has to do with generation and nutrition, 

 Dr. Beale has surnamed it " germinal matter." 



So far as can be discovered, there is no difference in chemical 

 composition between the protoplasm of one part or organism 

 and that of another. The movements which can be seen in 

 certain vegetable cells apparently belong to a substance which 

 is identical in composition with that which constitutes the 

 greater portion of the bodies of the lowest animals, and which 

 is present in greater or less quantity in all the living parts of 

 the highest. So much appears to be a fact ; that in all living 

 parts there exists an albuminous substance, in which in favor- 

 able cases for observation in vegetable and the lower animal 

 organisms, there can be noticed certain phenomena which are 

 not to be accounted for by physical impressions from without, 

 but are the result of inherent properties we call vital. For 

 example, if a hair of the Tradescantia Virginica, or of many 

 other plants, be examined under the microscope, there is seen 

 in each individual cell a movement of the protoplasmic con- 

 tents in a certain definite direction around the interior of the 

 cell. Each cell is a closed sac or bag, and its contents are 

 therefore quite cut off from the direct influence of any motive 

 power from without. The motion of the particles, moreover, 

 in a circuit around the interior of the cell, precludes the notion 

 of its being due to any other than those molecular changes 

 which we call vital. Again, in the lowest animals, whose 

 bodies resemble more than anything else a minute mass of 

 jelly, and which appear to be made up almost solely of this 

 albuminous protoplasm, there are movements in correspondence 

 with the needs of the organism, whether with respect to seiz- 

 ing food or any other purpose, which are unaccountable accord- 

 ing to any known physical laws, and can only be called vital. 



