2 1 6 ENDOPLAST AND PERIPLAST. 



so named, they found that it was neither white nor cell- 

 like. The desirableness of a change, if not in the nomen- 

 clature, at least in the method of treating the subject, has 

 long been felt, and of late years a change has become more 

 necessary ; for, in consequence of the many conflicting and 

 irreconcilable statements made in our most modern text 

 books of physiology and minute anatomy, the student has 

 found it impossible to deduce any general conclusions 

 concerning the mode of development and growth of the 

 tissues, and after wading through hundreds of pages with 

 the utmost diligence, he has been disappointed in his hopes, 

 and has failed to discover either fundamental principles or 

 general truths. 



The confusion, always considerable, was increased when, 

 in 1853, Huxley endeavoured to revive Wolff's idea, and 

 asserted that the cell-wall (" periplastic substance") was 

 active and formative, while the nucleus termed by him 

 " endoplast," was unimportant and accidental. The latter 

 is, nevertheless, the really active and the only living matter of 

 the cell, while the periplastic substance is passive. In 1868, 

 however, Mr. Huxley completely modified the views he had 

 taught upon this fundamental question, without offering one 

 word in explanation, or even stating that he had given up 

 the views he entertained with respect to the endoplast and 

 periplast. 



The meanings attached to the terms in general use were 

 so vague, that I felt I could not convey a clear idea of the 

 changes which I had demonstrated in the anatomical units 

 of the organism if I continued to employ them. It was 

 only right to insist upon the fundamental importance of the 

 absolute distinction between the active and the passive 



