MUSCULAR CHANGES. 527 



there will be noticed proceeding from the inside outward : First, 

 the congested blood vessels ; secondly, a zone of new-forming con- 

 nective tissue, in some instances containing new-forming blood 

 vessels; thirdly, a zone of leucocytes; fourthly, a zone of broken 

 down leucocytes and cells detritus ; fifthly, the coagulated fibrinous 

 exudate. All of these changes are shown more or less distinctly 

 in Plate IV. 



The vascular changes in the subcutaneous connective tissue 

 are very similar to those occurring in lung tissue affected with 

 contagious pleuropneumonia. The writer has noticed new for- 

 mation of connective tissue around the blood vessels in the lung, 

 especially in the vicinity of sequestra where the area involved 

 is being walled in by a fibrous capsule. The earlier vascular 

 changes of the subcutaneous tissue also simulate the changes 

 seen around the arteries and veins in affected lung tissue, also 

 the thrombi agree with those found in the veins of affected lung 

 tissue. 



The changes in the epimysium are very similar to those 

 observed in the subcutaneous connective tissue- The bands of 

 connective tissue surrounding the muscle bundles are markedly 

 distended with a fibrinous exudate, causing degeneration of the 

 connective-tissue fibers or pushing them to one side. The vas- 

 cular changes, also, correspond to those already described in the 

 subcutaneous tissue. 



One very striking lesion is the accumulation of leucocytes, in 

 various stages of degeneration, into foci and lines along the 

 margin of the epimysium. These take a deep stain and can thus 

 be traced with the unaided eye, forming very distinct lines which 

 mark off the borders of the epimysium as it extends through 

 the muscle tissue. This border of cells extends along the edges 

 nearest the muscle tissue, and even extends around the individual 

 muscle fibers, causing them to degenerate. The changes in 

 question are brought out distinctly in Plates I (a) and II (b). 

 These borders of cells correspond exactly with those found 

 along the edges of the interstitial tissue in lungs affected with 

 contagious pleuropneumonia, and are regarded by Smith (3) to 

 be one of the characteristic lesions of that disease. 



From the inner surface of the epimysium, septa are sent in 

 which divide the muscle into a number of large secondary bundles. 

 These septa are markedly distended with a fibrinous exudate 

 which may contain leucocytes scattered throughout. As a rule, 

 the leucocytes are thickest along the edges of the septa nearest 

 the muscle, simulating the line formation described above. 



