OVERGROWTH OF CONNECTIVE TISSUE. 129 



granulations," and I have succeeded in discovering an abundant 

 supply of nerve-fibres in an exquisite example of these sent to mo 

 bv Professor Billroth. 



2. Xox-Inflammatory Overgrowth of the Coxxective 



Tissue. 



§ 107. I have already (§ 85) relegated the hyperplastic 

 conditions of individual organs to the corresponding chapters of 

 the Special Part of this work, inasmuch as from a histological 

 point of view they do not furnish materials for any generalisa- 

 tion save only that they are quantitative excesses of normal 

 growth. Now the interstitial connective tissue forms an excep- 

 tion to this rule, because it is only a constituent of the various 

 organs, and not itself an organ, and because its increase by way 

 of overgrowth must therefore necessarily entail a qualitative 

 change in structure. Strictly speaking, a large proportion of 

 the processes included in the domain of interstitial inflammation 

 may also be viewed as consisting in an overgrowth (hyperplasia) 

 of the interstitial connective tissue. This applies especially to 

 inflammatory infiltration and the conversion of the infiltrated 

 products into connective tissue. In point of fact the non- 

 inflammatory differs from the inflammatory form of overgrowth 

 only by its slower rate of progress, if we set aside for a moment 

 all thought of its causation. A hyperiemic dilatation of the 

 vessels constitutes in every case the starting-point of the morbid 

 process. This is associated with an emigration of colourless 

 blood-corpuscles, which gives rise to an increase in bulk, a 

 thickening of the connective tissue. Especially noteworthy 

 is the extent to which the sheaths of the vessels arc in- 

 filtrated ; they often attain from three to five times their 

 normal thickness. The transformation of the infiltrated cells 

 into fibrillar connective tissue is a work of time, and seems in 

 many cases (kidneys, pia mater) not to occur at all. Mean- 

 while the close analogy between this process and inflammation 

 is self-evident, so that we cannot quarrel with authors and 

 practitioners for continuing to call it " clironic inflammation." 

 Wherever a definite source of irritation, e.g. a persistent or 

 often renewed, though feeble mechanical irritant is the cause of 



9 



