CHAPTER XI. 



THE protoplasmic theory of life was brought before 

 the general public in this country a few years ago, by 

 Mr. Huxley, but it was not properly appreciated or 

 understood, for some reasons which it is incumbent on 

 us to consider now. The anatomical unity of the living 

 matter, as stated in Mr. Huxley's lecture at Edinburgh, 

 in 1868, was objected to by his critic, the eminent 

 metaphysician Dr. Stirling, as only made out by keep- 

 ing out of sight essential physiological differences, for 

 if all life is identified in protoplasm, so also you must 

 differentiate all life in protoplasms ; and instead of all 

 kinds of protoplasm being interchangeable, as he 

 asserts was said by Huxley, there must be infinite 

 difference in power, form, and substance, among differ- 

 ent kinds of living matter. This is hardly warranted 

 by Huxley's words, and the diversity of the several 

 kinds of living matter is an essential part of the doc- 

 trine, not only of Fletcher and Beale, as we have seen, 

 but also of Hackel, who says :* " In short, all the im- 

 measurable variety in the most diverse properties of 



* "aenereUeMorpli.,"i. 277. 



