438 SUMMARY OF CURRENT RESEARCHES RELATING TO 



go to show that neither the removal of oxygen nor the hindering of the 

 giving off of carbon dioxide is able to throw cells into the state of 

 excitation. This state seen in moribund cells is not due to scarcity of 

 oxygen or to accumulation of carbon dioxide. Histological investiga- 

 tion shows that non-fatal doses of chloroform leave the cells in a resting 

 state. When the limit is passed the protoplasm of the cells passes into 

 the state of excitation, and death ensues. The protoplasmic changes 

 induced appear to be irreversible. The processes of excitation do not 

 depend on what takes place at the periphery or membrane of the cells. 



Nuclear Substance in Relation to Fibrous Elements.*— Gaylord 

 Swindle finds that the most important neuroglia-fibres arise by a meta- 

 morphosis of certain neuroglia nuclei. There are three kinds of 

 metamorphosis involved. 1. A finger-like bud on the surface of the 

 nucleus may grow out into a long fibre, the chromatin taking the form 

 of a funnel-shaped bundle of fibrils. The protoplasm does not play an 

 important role. 2. There may be a unipolar, or, more rarely, a bipolar 

 or multipolar elongation of small compact glia-nuclei. 3. A third type 

 of nuclear metamorphosis, in its earlier stages at least, is indirect 

 amitosis. A neuroglia-cell may assume a multipolarity, as complex as a 

 highly specialized ganglion-cell. Pseudopodia grow out in all directions, 

 but the energy is in most cases expended only in one bud, which takes 

 the form of a migratory vesicle. The whole elongated nerve-cell is 

 really multinuclear — there is a stationary nucleus, a migratory nucleus, 

 and the connecting nuclear cylinder with its protoplasmic sheath. 



Trophospongium and Reticular Apparatus in Spinal Ganglion 

 Cells, f — Einil Holmgren returns with fresh evidence to his thesis that 

 the intracellular " Saftkanalchen " are due to the liquefaction of 

 portions of a protoplasmic network or trophospongium, and that the 

 latter is the same as Golgi's " apparato reticolare." In the vegetative 

 life of the ganglion-cells the trophospongium extends as a network ; 

 under certain conditions portions become more or less fluid, forming 

 the canaliculi. The acidophilus contour of the canaliculi represents the 

 remains of the threads of the reticulum. Some remarkable figures are 

 given of spinal ganglion cells from the rabbit. 



Vitreous Humour in Amphibians and Reptiles. J — A. Syent- 

 Gyorgyi nas made a study of the vitreous humour, and of the histo- 

 logical and histo-topographical relations of its fibrillar portion, in the 

 eye of Amphibians and Reptiles. In all the Amphibians and Reptiles 

 investigated (and probably in all Vertebrates) the fibrillar portion of 

 the vitreous humour exhibits a special structure, characteristic for each 

 species, and constant down to the smallest details in the same form. 

 The zonula and the vitreous humour are not so sharply distinguished 

 from one another in Amphibians and Reptiles as in higher Vertebrates, 

 but in most forms they are separated by a. thickening of the vitreous 



* Anat. Anzeig., xlvi. (1914) pp. 149-51. 



t Anat. Anzeig., xlvi. (1914) pp. 127-38 (9 figs.). 



X Arch. Mikr. Anat., lxxxv. (1914) pp. 303-60 (5 pis. and 6 figs.). 



