828 THE NERVOUS SYSTEM. 



lesion in the spinal cord. The areas of sclerosis vary in size from that 

 of a pea to that of an almond. They may be few or numerous, they may 

 be white, grayish, or grayish-red in color, and are usually but not always 

 sharply outlined against the unaltered brain tissue. Although in many 

 cases the increase in the connective-tissue elements seems to be the pri- 

 mary lesion, and the degeneration of the nerve elements secondary to 

 this, it is quite possible that in some cases the increase in connective tis- 

 sue may be secondary to a degeneration of the nerve elements from loss 

 of nutrition or from other causes. 



There is reason for the belief that multiple sclerosis may sometimes be 

 the result of disseminated local necrotic lesions of acute infectious dis- 

 eases scarlatina, for example, occurring at an early period of life. ' 



Encephalitis in the New-Born. 



This condition, first described by Vircliow, is said to consist in the formation of 

 circumscribed collections of cells of various sizes containing many fat granules (granu- 

 lar corpuscles) and forming yellowish masses, from 1 mm. to 6 mm. in diameter, in the 

 brain tissue. A more diffuse occurrence of granular corpuscles is also described, but 

 this is said by some observers to be physiological. The nature of this lesion is but little 

 understood, and is still the subject of controversy. 



LESIONS OF THE BRAIN IN GENERAL PARESIS OF THE 

 INSANE. 



The changes in this disease are in the main those of chronic diffuse 

 encephalitis, but the appearances vary greatly and depend to some extent 

 upon whether the brain is examined in early or late stages of the disease. 

 A.ccording to Meyer, in the early stages of the disease the convolutions, 

 particularly of the anterior cerebral lobes, are swollen, the gray matter 

 is congested and softened in places. The brain tissue is more or less 

 infiltrated with leucocytes. Fatty degeneration of the walls of the 

 capillaries, and punctate haemorrhages, are also common. 



In later stages of the disease a great variety of changes may be ob- 

 served: hsemorrhagic pachymeiimgitis, thickening of the dura mater, 

 and close adhesions to the skull ; thickening and opacities of the pia 

 mater, adhesions of the latter to the dura mater and to the brain tissue. 

 The brain tissue is apt to be atrophied, is often very soft, and the ventri- 

 cles are dilated and filled with fluid. The pia mater may be cedematous, 

 the ependyma thickened and roughened. On microscopical examination 

 the neuroglia is found to be increased in amount, the ganglion cells are 

 shrunken and sometimes pigmented; the nerve fibres may also be 

 atrophied, and the blood-vessels in a condition of fatty orlryaline degen- 

 eration. There may be an accumulation of fatty and granular cells along 

 the walls of the blood-vessels. Secondary degenerations in the spinal 

 cord are not infrequently observed. a 



1 See Oppenheim, Berl. klin. Wochenschrift, March 3d, 1896. 



2 It is very difficult to make positive and definite statements regarding many such 

 lesions of the brain as those just indicated, or in general of brain lesions whose nature 



