DISEASES OF ARTERIES AND VEINS. 



247 



I refer to the striated lamella of Henle, which present them- 

 selves under a magnifying power of 500 diameters (fig. 78) as 

 finely striated, wavy layers of basis-substance (of connective 

 tissue), in whose interstices flattened, lenticular corpuscles are 

 embedded. In these cell-containing spaces, the opposed surfaces 

 of the basis-substance exhibit a peculiar, homogeneous lustre ; 

 moreover, they present a double contom', which makes each cell 

 appear as if surrounded by a special capsule. The plausibility 

 of this view is enhanced by the appearances presented in hori- 

 zontal sections (fig. 79) which show how closely this peculiar 

 property of the basis-substance is connected with the distribu- 



FiG. 79. 



J'lliiUiii ' 



^ ■ m 



Horizontal section through tlie inner coat of the aorta. For 

 explanation see text. ■^. 



tion of the cells. The ceil-contaming spaces appear of a stellate 

 form, with branching prolongations which anastomose with one 

 another. The whole arrangement reminds us very forcibly of 

 the cell-containing capsules of cartilage. But can we be sure 

 that the stellate capsules of the intima are really closed cavities ? 

 For it is undoubtedly true that in those morbid products which 

 spring from the intima, the newly-developed cells are found out- 

 side the ^^ connective-tissue corpuscles," as well as within them ; 

 this forces us upon the horns of a dilemma; for either they 

 cannot have sprung from these connective-tissue corpuscles, or 

 else they must have escaped from the capsules. We may pro- 

 visionally regard them as leucocytes which have migrated from 

 the blood. 



The structure of the intima lias not hitherto received the 

 attention which it merits ; on this ground, and also with a view 

 to its diseases, which we are about to consider, I have lingered 



