40 FUNDAMENTAL STRUCTURE OF PROTOPLASM 



cannot be removed even by prolonged extraction with organic solvents, 

 such as ether or benzene, unless the complex is severely disrupted (3). 



There are, on the other hand, a great number of evidences that 

 the protoplasm is composed of granules. As described in the previous 

 part, protoplasm is readily decomposed into virus-like particles. On 

 the administration of a proper stimulus it will begin to coagulate into 

 minute particles at the site of stimulation. The coagulation thus in- 

 duced will be successively transmitted to other parts. 



Thus, on the one hand, protoplasm appears to be composed of 

 fibrillar elements, while on the other hand, it appears to be granules in 

 the nature. Actually many granular elements such as mitochondria and 

 microsomes are known to be present in abundance in the protoplasm, 

 and hence a series of workers postulated the corpuscular theories of 

 protoplasm, insisting on its granular nature ; among them Butschli's 

 foam structure or honeycomb theory is well known. Frey-Wyssling 

 insisted, however, that all hypothesis as regards plasm structure which 

 postulate distinct submicroscopic particles, such as granules, droplets, 

 alveoles, and ultramicrons, must be discarded as being corpuscular 

 theories (4). 



Although these two concepts regarding protoplasm structure m.ay 

 seem incompatible with each other, in the opinion of the writer they 

 are never contradictory. According to the writer's theory the struc- 

 ture of protoplasm is as follows: In protoplasm, extended thread-like 

 protein molecules of globulin nature make up bundles, and such bun- 

 dles or corpuscles composed of parallel alignment of thread-like protein 

 molecules represent the unit component of protoplasm. The writer 

 has proposed the name ''elementary body of protoplasm" to this unit. 

 Lipids may be interposed among the protein threads as indicated by 

 I in Fig. 4. If protein molecules combine directly with one another, a 

 solid crystal may result ; but owing to this lipid interposition, the ele- 

 mentary body may be able to exist in a liquid crystalline state. 



Such elementary bodies or bundles of protein threads constitute the 

 protoplams in forming in tern a parallel array joined by a loose junc- 

 tion end to end as well as side by side, so that, protopasm is on the 

 whole also a kind of liquid crystal. The elementary body may be lia- 

 ble to be decomposed into several thinner bundles, /. e., "elementary 

 bundles" as shown in Fig. 5 ; in other words, several elementary bun- 

 dles form a thicker bundle, /. e. an elementary body. 



The extended protoplasm proteins tend to be contracted when 

 certain physical or chemical effects are given as stimuli. Elementary 

 bodies may be coagulated into separate particles following such con- 

 traction of protoplasm proteins. 



On account of the orderly association of protein molecules just 



