384 INFLAMMATION. 



" granular " stage of indifference. Usually such a change occurs 

 without a preceding coalescence of corpuscles into territories. 

 Many of the indifferent corpuscles become infiltrated with basis- 

 substance j but we do not know whether this is of a gelatinous 

 or chondrogenous character. Some, however, remain free from 

 infiltration, at least in their central portions, and in this condition 

 constitute the cartilage corpuscles which are found lying at 

 nearly regular intervals throughout the newly formed basis- 

 substance. In the second week after the injury, we invariably 

 encounter nests of inflammatory corpuscles lying around a cen- 

 tral blood-vessel. The corpuscles nearest the vessel are more 

 globular, while the more distant ones are elongated and fusiform ; 

 we are able to trace all the stages of transition, from a uniformly 

 reticular bioplasson into an apparently structureless basis-sub- 

 stance. (See Fig. 161.) 



In the above-mentioned groups or nests of inflammatory ele- 

 ments we observe the transformation of capillary blood-vessels 

 into solid cords, and subsequently the division of these into 

 smaller medullary corpuscles, which in turn also share in the 

 production of cartilage. This process is similar to the transmu- 

 tation in advancing age of capillaries into tissue. 



The newly formed basis-substance of the provisional callus is 

 in part hyaline and in part striated. The striations are produced 

 either by the preservation of the boundary lines of the former 

 fusiform, indifferent elements, or by a splitting of these elements 

 into small spindles, within the territory, before the infiltration 

 with basis-substance had taken place. We notice bioplasson 

 bodies at regular intervals, which in this stage deserve the name 

 of cartilage corpuscles ; they vary greatly both in size and ap- 

 pearance. In some cavities of the basis-substance we encounter 

 large, pale, nucleated plastids ; in others, smaller, shining lumps, 

 usually with vacuoles ; and in other cavities plastids are found 

 which are composed of a varying number of lumps of different 

 size. Lastly, very small cavities are seen in the basis-substance, 

 containing only a single yellowish, bright lump. All plastids, 

 whatever may be their size and shape, exhibit a distinct reticular 

 bioplasson structure, whenever they are nucleated ; all granules 

 and lumps contained in a plastid are likewise interconnected, and 

 from all plastids, without exception, delicate radiating spokes 

 arise, which penetrate the surrounding narrow rim, and are lost 

 in the basis-substance. (See Fig. 162.) 



The newly formed cartilage of the provisional callus corre- 



