28 THE SCIENCE OF LIFE. 



although the first bioplasmic particle subdivides itself 

 into an aggregation of similar particles or cells, yet there 

 soon appears a structural differentiation of organs for 

 special uses, which is more elaborate and heterogeneous 

 as the type approaches the human structure. A single 

 cell or living particle, however, in any structure is, to all 

 intents and purposes, a living thing, and possesses pow- 

 ers of assimilation, growth, and reproduction, altogether 

 different from the mineral or non-living body. 



6. Living matter, or bioplasm, may be considered 

 physically as a peculiar compound of the chemical 

 elements carbon, oxygen, nitrogen, and hydrogen, 

 called by Mulder Proteine, and by Mr. Huxley and the 

 German histologists Protoplasm, or the physical basis of 

 life. It is nearly identical with Albumen. So far as is 

 known, this combination of elements is always the prod- 

 uct of pre-existing, living matter. It has never been 

 produced in the laboratory, and if it were possible for a 

 chemist to manufacture albuminoid matter, or proto- 

 plasm, it would be dead protoplasm, and not bioplasm, 

 and would be destitute of vital properties. Other con- 

 ditions are necessary to vital phenomena besides com- 

 bination of material elements. Light, heat, electricity, 

 and moisture are all necessary conditions ; nor these 

 alone, for with all these existing and active, the proto- 

 plasm may not live. Some other factor is essential to life 

 besides matter and physical force, as we said in the last 

 chapter. The term bioplasm is well applied to express 

 matter in its living state, while protoplasm should be 

 restricted to the material itself. 



7. The essential phenomena of living matter next 



