22 THE CELL 



His opinion is based upon his experiments on living objects, which 

 he treated with various reagents. In his opinion there is a frame- 

 work of plasma corresponding to the lamella? of oil, which, in the 

 artificial emulsion, separate the droplets of fluid from one another. 

 Similarly here also granules (microsomes) are collected together at 

 the points of intersection. Further the protoplasmic body is fre- 

 quently differentiated externally to form an alveolar layer. The 

 appearance, described by other observers as a thread or net-like 

 structure with spaces which communicate and contain fluid, 

 Butschli considers to be due to the presence of a froth or honey- 

 comb structure, in which the cavities are closed in on all sides ; he 

 himself, however, remarks that, in consequence of the minuteness 

 of the structures in question, it is impossible to decide finally, 

 simply by the appearance under the microscope, whether a net-like 

 or honeycomb structure really exists (II. 7b, p. 140), since " in 

 either case the appearance under the microscope is the same." 



Now it seems hardly justifiable, that this similarity to an 

 artificially prepared froth, although it has caused Butschli 

 finally to make up his mind, should be allowed to settle the 

 question. 



Two objections to this theory of Biitschli's must be mentioned. 

 The first is that it does not apply to nuclear substance, which 

 without doubt is similar in its organisation to protoplasm. For 

 during the process of nuclear division threadlike arrangements in 

 the form of spindle- threads and nuclein-threads are so distinctly to 

 be seen, that their existence certainly cannot be questioned by 

 any one. 



The second objection is more theoretical in nature. The oil 

 lamellae are composed of a fluid which does not mix with water. 

 Now if the comparison between the structure of this emulsion and 

 that of protoplasm is to depend upon something more than a mere 

 superficial similarity, the plasma lamellae, corresponding to the 

 oil lamellae, must be composed of a solution of albumen or of liquid 

 albumen. Now this cannot be the case, for a solution of albumen 

 is capable of mixing with water, and hence would of necessity mix 

 with the contents of the spaces ; hence the albuminous froth would 

 have to be prepared with air. In order to get over this difficulty, 

 Butschli assumes that the chemical basis of the framework sub- 

 stance is a fluid, composed of molecules of albumen combined with 

 those of a fatty acid (II. 7b, p. 199) ; this supposition, and 

 especially the theory that the framework substance is a fluid, is 



