200 CONNECTIVE TISSUE. 



the knee-joint, and in this way obtained the condyles, as it were, 

 on a handle formed by the stump of the femur. After the syno- 

 via was washed off, I rubbed a stick of nitrate of silver for several 

 minutes over the eondyles, transferred the specimen to water, and 

 exposed it to daylight. After a few days, the parts which had 

 been brought in contact with the re-agent became dark brown. 

 The most superficial layer was removed as useless, and the next 

 layer was examined. I would remark that sections from deeper 

 portions, which at first are but slightly tinted by the silver-salt, 

 assume a deep color on exposure to daylight. The deeper layers 

 of the condyle, too, are dyed brown, and to a certain depth are 

 well adapted for new sections. 



The following description is that of specimens taken from 

 the condyles of a young and an old dog : they showed the same 

 features. 



From the stained specimens taken from the anterior and 

 under portions of the condyle, I could obtain nothing satisfactory 

 for establishing the idea of a reticular structure. As soon, how- 

 ever, as I reached the lateral surface, close to the edge, the aspect 

 of things at once became changed. (See Fig. 75.) 



The basis-substance at the borders of the cartilage cavities 

 is stained dark brown, in other portions light brown-red. From 

 the cavities of varying shapes light offshoots are thrown out in 

 different directions, which may be grouped in three orders, 

 according to their calibers. The broadest offshoots, those of the 

 first order, either connect cartilage cavities, or run merely into 

 the basis-substance. The somewhat narrower offshoots, those 

 of the second order, project from either the cartilage cavities or 

 the broader offshoots, and ramify freely into the very narrow 

 ones, those of the third order. The latter shoot out from the 

 cartilage cavities and the processes of the first and second order, 

 as well as from the ends of coarser processes, and traverse the 

 basis-substance throughout. Thus a rich, extremely delicate 

 reticulum of light, irregular lines is produced, with numerous 

 varicose enlargements, the meshes of which reticulum are filled 

 with the brown basis- substance. In the cavities we recognize 

 the dim, unstained cell-bodies, with their enlarged, thorny nuclei 

 and their offshoots, which are traceable into the processes of the 

 cavities of the first order. 



In specimens taken from the anterior and under surface of 

 the condyles, offshoots of the third, and occasionally some of the 

 second, order are found, which are readily distinguished, wherever 



