PARTIAL ANJEMIA OF THE BRAIN. 205 



nate obstructions of the vessels, the softening is usually in the greatei 

 hemispheres and chiefly in their medullary substance. It varies in 

 size from that of a bean to a hen's egg. The grade of the softening 

 differs. In the highest grades the cerebral substance, at the point of 

 necrosis, is found changed to a moist, gelatinous trembling pulp. The 

 color of the softened point is sometimes white or grayish-white, some- 

 times more yellowish. In the former case there is usually a reddish 

 tint about the periphery, due partly to dilatation, partly to rupture of 

 the capillaries and escape of blood from them. In the first of the 

 three forms of partial ansemia which we have described, that due to 

 thrombosis or embolism of a cerebral artery, on autopsy we do not find 

 the parts supplied by the plugged artery remarkably pale, but they 

 are not unfrequently studded with small capillary haemorrhages, par- 

 ticularly at the periphery. This exactly corresponds with what is 

 found in other organs when there is stoppage of the vessels by throm- 

 ses or emboli ; but, as we said when speaking of haemorrhagic infarc- 

 tions of the lung, it is difficult to explain. On account of the difficulty 

 of deciding whether a portion of brain has been anaemic during life, 

 we should make it a rule to seek most carefully for any obstruction of 

 the cerebral arteries, particularly of the arteria fossae Sylvii, in any 

 cases where the patient has died from a chronic brain disease or from 

 an acute one beginning with a sudden occurrence of hemiplegia, unless 

 the autopsy gives some other satisfactory explanation of the symp- 

 toms. Before attention was called to the occurrence of this anomaly, 

 autopsy, in cases of severe brain-disease with hemiplegia, often fur- 

 nished nothing satisfactory. There was nothing left but to suspect an 

 " intravascular apoplexy," which did not at all explain the occurrence 

 of the hemiplegia. The yellow color of the affected part often de- 

 pends on this capillary haemorrhage, and is due to the infiltration of 

 the disintegrated brain-substance with escaped and altered coloring 

 matter of the blood. After the disease has existed some time, we 

 find the affected part changed to a cellular network filled with a 

 chalky, milky fluid (Durand-FardeV s infiltration celluleuse). On 

 microscopical examination of necrosed portions of brain, we usually 

 find only remains of nerve-filaments, granular cells, which correspond 

 to the ganglion-cells or neuroglia-nuclei that have undergone fatty 

 degeneration, coloring matter, and masses of detritus. 



Partial anaemia of the brain caused by collateral oedema, occurring 

 in the vicinity of circumscribed disease, can occasionally be recognized 

 on autopsy by the affected part having a peculiar moist lustre and di- 

 minished resistance, as well as by its becoming very slightly promi- 

 nent on a section through the brain. When the disease is more se- 

 vere, the brain-substance is still more relaxed, and finally a state maj 



