INFLAMMA TION. 



385 



spends in its structure with normal hyaline or striated cartilage. 

 A striking difference, however, is displayed in the tissue of the 

 provisional callus by the large amount of bioplasson it contains. 

 The coarse granulation of even the nucleated plastids j the 

 masses of bioplasson lumps lying in the cavities j the presence 

 of single compact and vacuoled 

 lumps in many of the cavities are all 

 unquestionably due to the great 

 augmentation of living matter pro- 

 duced by the inflammatory process. 

 Such irregular formations are never 

 met with in normal hyaline or stri- 

 ated cartilage. They can be ex- 

 plained only by the different phases 

 of development which the bioplasson 

 lumps undergo. (See page 46.) 



That the newly formed cartilage 

 has really to a great extent sprung 

 from former periosteal tissue is 

 proved by the presence of unchanged 

 elastic fibers. The cartilage tissue 

 is traversed by a varying number 

 of single, sometimes bifurcating, 

 straight, glistening fibers, which 

 either divide the tissue into more or 

 less regular rhomboidal fields, or are 

 scattered through it without uni- 

 formity. There is scarcely any doubt 

 that these elastic fibers originally 

 belonged to the periosteal tissue, 

 and remained unaltered by the in- 

 flammatory process. They also con- 

 tinue unchanged even after calcifi- 

 cation of the cartilaginous tissue 

 has taken place nay, even after this tissue has retrogressed to 

 the medullary state, the fibers often traversing the newly formed 

 medullary spaces without any apparent regularity. 



In the third week after the fracture, a calcareous deposition 

 takes place in the tissue of the provisional callus. Its extent varies 

 greatly in different individuals, and sometimes it is very scanty, 

 though never entirely wanting. In the fractured humerus of 

 a child, during the fourth week after the injury, the calcifica- 

 25 



FIG. 1 62. CARTILAGINOUS CAL- 

 LUS, FOURTEEN DAYS AFTER 

 THE SUBCUTANEOUS FRACT- 

 URE OF THE TIBIA OF AN 



OLD CAT. CHROMIC ACID 

 SPECIMEN. [PUBLISHED IN 

 1873.] 



a, plastic! with several formations 

 like nuclei; ft, vacuoled, shining plas- 

 tid ; c, plastid, composed of numerous 

 small, bright granules and lumps; d, 

 minute bioplasson lump in a cavity of 

 basis-substance. Magnified 800 diam- 

 eters. 



