lO 



THE NEW CELL DOCTRINE 



at more or less regular distances from one another, and also 

 protoplasm which forms an open network. The meshes of this 

 net contain a fluid, which is usually not interpreted as a part 

 of the tissue proper, just as the fluids, for example, which we 

 find in the articular cavities or in the body cavity of the adult 

 are not reckoned as tissues of the body. In vertebrates, in 

 which the protoplasm of the network of the mesenchyma has 

 been chiefly studied, we find that the network is at first 

 extremely irregular; but early, as development progresses, the 

 protoplasm accumulates in parts around the single nuclei and 



1 



,^i<i?in(i''-- 



Fig. 8. — Hyaline cartilage of a human embryo. Between the cells the firm basal 

 substance of the cartilage is developed in large quantities. — After J. Sabotta. X280. 



forms, so to speak, a court of protoplasm around every nucleus. 

 From each court radiate the threads of protoplasm, which 

 estabhsh the connection with the neighboring courts, and thus 

 the mesenchyma remains a network stiU. These two forms 

 of tissue, which are characteristic for the connection or fusion 

 of cells, we call syncytium. On tracing the development 



