THE IDENTITY OF NEUROGLIA. 



547 



swollen, even globular in outline." The extensions were also 

 thicker and more nodular. "Are these elements, which belong 

 to the lymphatic apparatus," queries the author, "taking up 

 detritus from the degenerating protoplasm of the nerve-cells 

 and becoming engorged?" The conclusion that they belonged 

 to the lymphatic system was reached because they were found 

 to contain lymph, which, in the language of Johannes Miiller, 

 is "blood without its red corpuscles": i.e., Hood-plasma, and, 

 of course, its due proportion of oxidizing substance. 



Evidently then, it is the plasma found in the capillaries 

 of cellular elements of all organs which, crowded by excessive 

 back-pressure (due to the marked contraction of the central 

 vascular trunks induced by the poisons), causes the endothelial 

 plates or cells constituting the walls of what Berkley terms the 

 "intermediary vessels" to look, using his words, "as if they 

 had been subjected to severe strain" as their even walls have 

 "many irregular bulges in their outlines." That the neuroglia- 

 fibers are the channels through which it is transmitted is also 

 suggested by a remark made in connection with the effects on 

 the gemmules, the retention of which, writes Berkley, "clearly 

 shows that the swelling comes from within the substance of the 

 stem and pushes the gemmulse, which are still adherent, out- 

 wardly and apart." 



Does a direct connection between the neuroglia-fibers and 

 the protoplasmic processes of neurons exist, as suggested by 

 the fact that Apathy's neuro-fibrils are stated by him to pene- 

 trate the cell-bodies provided his fibrils are glia-fibers? To 

 establish this upon a firm basis, the thickening, bulging, etc., 

 found by Berkley upon the vascular neuroglia must also be 

 shown to extend to the processes of the neuron. 



Golgi has expressed the opinion that the greater part of 

 the nerve-cell i.e., the entire structure excepting the axis- 

 cylinder was concerned with its nutrition: a view which met 

 with considerable dissension. Among the opponents of this 

 interpretation was Forel, 43 who contended that the entire cell 

 was simultaneously endowed with nutritional and functional 

 attributes. This conception was defended by Ramon y Cajal, 



* Forel: Archiv fUr Psychiatrie und Nervenheilkunde, vol. 1887. 



