130 H. E. JOEDAN 



in the islet cells of the pancreas of the guinea-pig as a network 

 of canals (p. 365), while Gatenby ('19) considers both Golgi 

 apparatus and mitochondria to consist of a substance of living 

 protoplasm denser than the surrounding medium in which they 

 lie (p. 115). 



E. V. Cowdry ('21) suggests the terminology 'reticular mate- 

 rial' for the so-called Golgi apparatus, in view^ of our limited 

 knowledge regarding its intimate structure. He describes it 

 as a restricted area of fluidity in the cytoplasm (p. 8). His 

 observations on this 'material' in the erythroblasts, leucocytes 

 and lymphocytes of the red marrow of the guinea-pig lead him 

 to the tentative conclusion that it is of a 'watery consistency, 

 being even more fluid than the general ground substance, and 

 is probably changing its form continually as it plays its obscure 

 part in the activities of the cell, for no two networks as seen 

 in fixed preparations of blood cells, or any other kind of cell, 

 are exactly alike' (p. 7) . 



jNIy own observations incline me to an interpretation of the 

 Golgi apparatus in terms of solid fibrils rather than of canaliculi; 

 at least 'solid' in a manner similar to the constitution of the mito- 

 chondria and that of the eosinophilic granules of the leucocytes. 

 In some of the preparations the latter granules are deeply stained 

 by the osmic acid, like the mitochondria of other preparations, 

 and appear solid. In other preparations, where the mitochondria 

 have become visible by the reaction to osmic acid, the eosino- 

 philic granules have been dissolved, leaving only spherical 

 vacuoles. In a similar fashion, the presumably solid Golgi 

 net may be conceived to become in certain instances a system of 

 canaliculi by the solution of fibrils, leaving behind the cyto- 

 plasmic mold of which the 'fibrils' formed the cast. The chang- 

 ing form and character of the Golgi apparatus would be the 

 consequence of the continual addition of new portions (mito- 

 chondria?) and the continual destruction or resorption of other 

 portions. 



