CELL CONTENTS 91 



These are of two kinds, the protoplasmic inclusions and the deuto- 

 plasmic inclusions. The former are characterised by their uni- 

 versaHty in cells, their permanence in the cell-cycle and by the 

 fact that they appear to be definitely active organs in the cells. 

 The deutoplasmic inclusions differ in kind between different cells ; 

 they are transitory in the cell-cycle, and they are easily recognis- 

 able as passive structures in the cells. 



The protoplasmic inclusions are the Golgi apparatus, the 

 mitocho7idria, the central apparatus, and possibly the structures, 

 known as chromidia, whose relationship to the other inclusions is 

 doubtful. Evidence will be brought forward to show that another 

 system known as the " vacuome " may have to be considered as 

 a protoplasmic inclusion, although the knowledge concerning it 

 does not warrant any final opinion. The Golgi apparatus, if of the 

 diffuse type, may have modified cytoplasm associated with it. In 

 this case this cytoplasm is termed the idiosome, and the Golgi 

 material attached to it the dictyosome. 



The central apparatus consists of three parts : the central 

 bodies or centrioles, the " heller Hof" and the sphere or attraction 

 sphere. Owing to a temporary association of the Golgi apparatus, 

 in certain cases only, with the central apparatus confusion has 

 occurred, and the idiosome has frequently been termed the 

 archoplasm or sphere material. There is no real connection 

 between the two organs such as is suggested by these names. 



The deutoplasmic inclusions are " non-living " granules of the 

 secretory type, e.g., fat, yolk, oil droplets, mucous and serous 

 globules, glycogen granules, etc. They are definitely the end 

 products of the metabolic activity of the cell, and do not take any 

 formative part in that metabolism. The protoplasmic inclusions, 

 however, as it will be shown later, are actively engaged in these 

 metabolic processes. 



The chief advances have been made in connection with the 

 Golgi apparatus, its structure and function, and while some very 

 definite facts have emerged in connection with this, it must be 

 repeated that the most important outcome of the investigations 

 on this and on the cell structures and functions is a general 

 clearing of the air with regard to definition, technique and possible 



