THE PRESENT POSITION OF CELL-THEORY. 235 



I may now anticipate the objection which is certain to 

 be raised that the visible and invisible structure which I 

 assign to protoplasm is utterly inadequate to explain the 

 phenomena of life. It is inadequate and it is intended to 

 be inadequate. Were I to pretend that it is adequate I 

 should be running counter to all the lessons taught by our 

 experience of living things. The structure which I have 

 assigned to protoplasm applies particularly to that simplest 

 known form of it which we rarely meet with, but which we 

 do meet with in exceptional cases, for instance in the pseudo- 

 podia of Gromia dujardini. But separate a protoplasmic 

 corpuscle formed by the thickenings of the thread-like pseu- 

 dopodia of this species from the rest of the animal ; the cor- 

 puscle separated is not any longer capable of an indepen- 

 dent existence, it soon perishes, it has all the structure 

 which I have described, but it is not capable of in- 

 dependent life. Clearly then life is not the outcome of this 

 structure, though the structure may play its part, and no 

 unimportant part in the life processes. 



When I have been speaking of protoplasm I have 

 obviously been confining my attention to that form of it 

 which is now generally distinguished under the name of 

 Cytoplasm. Cytoplasm taken by itself is not living matter 

 in the sense that it is capable by itself of maintaining an 

 independent existence. The experiments of Nussbaum, 1 of 

 A. Gruber and Verworn, confirmed by other observers, have 



a l'auteur (Nageli) ses Micelles. Leur constitution, leurs proprietes n'ont 

 rien que de tres admissible. Bien que leur mode de generation ne soit 

 guere probable, il n'y a aucune raison positive pour le repousser. Mais 

 l'arrangement des micelles et la structure de l'idioplasma sont invraisem- 

 blables au plus haut point. Nous avons demontre, au cours de notre 

 expose, que cet arrangement n'est pas de tout, com me l'auteur l'avance, le 

 resultat necessaire du seul jeu des forces moleculaires initiates ce n'est 

 qu'a grand renfort d' hypotheses etagees l'un sur les autres qu'il arrive a 

 faire disposer les Micelles en Files, les Files en Faisceaux, les Faisceaux en 

 Cordons et les Cordons en un Reseau repandu dans tout l'organisme." 



1 It was Nussbaum who first introduced the method of dividing in- 

 fusoria by artificial means, and the credit of having devised this very useful 

 class of experiment belongs to him. In my previous article I inadvertently 

 assign it to Gruber. 



