416 



LECTURE XVII. 



These changes can be best followed in those structures 

 which must on the whole be regarded as the most fre- 

 quent and the earliest seat of this change, namely the 

 smallest arteries. These first undergo the transformation, 

 and only after the constitution of their walls has become 

 changed, is the infiltration wont to extend to the sur- 

 rounding parenchyma, until at last the whole district of 

 tissue to which the artery leads has experienced the 

 change. If in an amyloid spleen we trace one of these 

 small arteries, whilst it breaks up into so-called penicillus, 

 we see how its wall, in itself already a thick one, becomes 

 thicker in proportion as the change advances, and how 

 at the same time the calibre of the vessel becomes con- 



FIG. 121. 



siderably diminished. This accounts for the circum- 

 stance, that all organs which experience the amyloid 

 change in a considerable degree, look extremely pale ; an 



FIG. 121. Amyloid degeneration of a small artery from the submucous tissue of 

 the intestine, with its trunk still intact. 300 diameters. 



large numbers in these plexuses indeed it seems to me doubtful whether they are 

 ever formed there. The concentric corpuscles which Schmidt examined were 

 therefore probably those sabulous bodies (Sandkorper acervulus cerebri, brain- 

 sand) which are nearly always present in the choroid plexuses and so greatly re- 

 semble the corpora amylacea in structure, that they were actually taken by Remac 

 to be such. Schmidt, thinking he had the same substance before him in the spleen, 

 published his two analyses with the idea that he was thereby furnishing a doubly 

 strong proof of the albuminous nature of this animal amyloid substance. From a 

 MS. Note by the Author. 



