8 PATHOLOGICAL MYCOLOGY. 



feebly. The reason of this sequence of phenomena is, that after 

 attaining their maximum degree of development in a locally devitalised 

 portion of tissue, the micrococci are prevented from further progress 

 by the zone of fully vitalised tissue around ; and the powerful vital 

 reaction in this zone hems in the organisms on every side, and at the 

 same time limits the formation of pus to the centre of the affected 

 locality. The micrococci soon exhaust all the supplies of pabu- 

 lum at their command, and then rapidly die out, being in many 

 cases destroyed by their own effete products in the pus ; and in pus 

 taken from long unopened abscesses they have quite disappeared. 

 Thus the presence of micrococci in the tissues precedes the reaction- 

 ary changes to which they give rise locally in the case of acute 

 abscesses. It is an easy enough matter to say that the tissues in 

 which the abscess formed had been devitalised by a blow or by 

 exposure to cold. Either of these, or both, may be cited as the 

 cause, but how do the micro-organisms come to be present in the 

 body ? Have the altered conditions of internal surfaces nothing to do 

 with this ? Have altered secretions and accumulations of excreta 

 played no part in the introduction of the foreign organism ? In fact, 

 under the above conditions, have not numerous organisms from time 

 to time been introduced into the tissues, but so long as the vitality 

 of these tissues was above a certain standard, the " germs " were 

 paralysed or destroyed, and no harm resulted ? In those conditions, 

 however, in which abscess formation is met with, these organisms 

 have sought out the devitalised point and have attacked it, and 

 there is a contest between the weakened tissue and the micro- 

 organism. There results an enormous proliferation of cells, many 

 of which become devitalised, and form pus, whilst those at the 

 margin of the abscess of higher vitality prove too strong for the 

 micrococci, and the abscess remains localised. By what means 

 the micro-organism retains its vitality until it reaches the weak 

 point is at present merely a matter of conjecture. Is it simply 

 paralysed, or is it passed rapidly to a spot in which it can live or 

 flourish, or is it so protected by the material in which it had origi- 

 nally flourished, or by other micro-organisms which, themselves dying, 

 still serve as shields to those which arrive at their destination ? This, 

 and numerous other most interesting questions, still await solution. 



