498 LECTURE XIX. 



tion, chiefly depends upon whether the basis-substance 

 which surrounds the young cells, becomes completely 

 fluid. If it retains a certain degree of consistence, the 

 process is confined to the production of granulations, and 

 these may just as well proceed from a surface whose 

 continuity is perfect, as from one where there is a breach 

 of it. In surgery it is generally assumed that granula- 

 tions form upon the walls of the breach occasioned by a 

 loss of substance, but in every case they arise directly 

 out of the tissue. They are found directly seated upon 

 bone without any loss of substance in it having preceded 

 them. They are found also in direct contact with the 

 cutis under the intact epidermis, and with mucous mem- 

 branes. Only in proportion as they become developed, 

 do the mucous membranes lose their normal character. 



Every development of the kind gives rise, as it pro- 

 ceeds, to separate masses (foci Heerde) of new tissue, 

 just in the same way indeed that growing cartilage 

 produces, in the immediate vicinity of the margin of 

 ossification, those large groups of cells (Fig. 124), each 

 of which corresponds to a single pre-existing cartilage- 

 cell. We have in fact to do with a process which finds 

 its counterpart in the ordinary phenomena of growth. 

 As a cartilage, when it does not calcify, as for example, 

 in rickets, at last becomes so moveable that it can no 

 longer perform its functions as a supporting structure, 

 so we see everywhere that the firmness of a tissue gra- 

 dually disappears through the development of granula- 

 tions, and during suppuration. However different there- 

 fore these processes of destruction apparently are from the 

 processes of growth, at a certain point nevertheless 

 they entirely coincide. There is a stage, when it is im- 

 possible to decide with certainty, whether we have in a 

 part to deal with simple processes of growth, or with the 

 development of a heteroplastic, destructive form. 



