318 HOW TO WORK 



To include these the definition must be totally changed. The 

 difficulty of including many bodies under the old definition, com- 

 bined with an implicit faith in its truth, has led many observers to 

 affirm the existence of a cell-wall, although none was present, and at 

 last the supporters of the old cell doctrine have taken refuge in the 

 idea that the ' cell-wair may itself be fluid and capable of running 

 together like the film of a soap bubble ! 



The moving matter of the white blood corpuscles, the granular 

 matter around the so-called nuclei of muscle, the contents (in part 

 or entire) of the vegetable cell have been called ' protoplasm,' but 

 those who have employed this word have not accurately defined 

 what they desire to include under it. The nucleus still seems to 

 be regarded as an object distinct from other parts of the cell which 

 has certain special functions assigned to it. 



It should also be remarked that the meaning of many of the 

 terms generally employed in describing the structure of, and the 

 changes taking place in, cells, undergo great modifications from year 

 to year, and thus is added another source of ambiguity and con- 

 fusion. 



To avoid entering into a long and tedious discussion as to the 

 meaning which should be assigned to the words in general use, I have 

 been led to use new terms when speaking of the essentially different 

 parts of the cell or tissue. I apply the term germinal matter only to 

 that which lives, changes, converts, germinates, &c. Formed material, 

 on the other hand, never possesses any of these properties. It has 

 lived, but is now lifeless ; it may be changed, but it cannot change 

 itself. In nutrition lifeless pabulum becomes living germinal matter, 

 which becomes in its turn formed material, cell wall or intercellular 

 substance, as the case may be. This last may accumulate or it may 

 be formed in a fluid state, and disintegrated as fast as it is produced. 

 The really important point is, that formed material of every kind 

 was once germinal matter, and that new formed matter is deposited 

 in one definite direction only, from the centre or from within, so 

 that in an ordinary simple cell, the germinal matter is invariably 

 within, then comes the recently produced formed material, and lastly 

 the oldest formed material, which is therefore most external. 



The views above given will be readily understood if the figures 

 appended be attentively examined. At a, the smallest visible particles 

 of germinal matter are represented, b. Small collections of germinal 

 matter, with a little formed material between them (as in mucus). 

 In one, portions are seen to project, and if these were detached each 

 one would grow and give rise to new masses, c. A mass of germinal 

 matter, with a very thin layer of formed material on its external 



