140 ORGANISED FLUIDS. 



the mischief sustained, and which it does by the elaboration 

 of pus corpuscles capable of being transformed into a pro- 

 tecting epithelium. 



In support of this view reference may be made to the fact 

 that it is by no means uncommon to encounter epithelial 

 scales mixed up with the ordinary pus corpuscles contained 

 within the cavity of an abscdbs, or covering the surface of an 

 old ulcer. 



But it may be asked how happens it then that all pus cor- 

 puscles do not become converted into epithelial scales, and 

 that so many of them are discharged or thrown off from the 

 system without attaining to the higher degree of development 

 of which they are stated to be susceptible. 



This arrest of development doubtless arises from the ra- 

 pidity with which the pus corpuscles are formed, and which is 

 indicative of the strength of the Vis medicatrix natures, the 

 result of which is that the earlier formed corpuscles become 

 displaced by the more recently developed ones, and are thus 

 removed without the sphere of growth, in consequence of 

 which they perish. 



Having thus considered the nature of pus corpuscles, we 

 will next endeavour to form some opinion in reference to 

 their origin and mode of formation ; in these respects also an 

 essential correspondence doubtless exists between pus and 

 mucous globules. 



Mandl attributes to the pus globule the same mode of 

 formation which he has described as belonging to the white 

 corpuscles of the blood, that is, that they are formed external 

 to the vessels by the aggregation of molecules precipitated 

 from the fibrin, and hence Mandl terms both the white and 

 pus corpuscles " fibrinous globules." 



This view of the formation of pus corpuscles is supported 

 also by the observations of Vogel (already cited) made upon 

 abraded surfaces. 



Mandl, therefore, is most probably correct in his opinion 

 as to the mode of formation of pus corpuscles, viz. by pre- 

 cipitation, but it is at the same time almost certain that they 

 are not constituted of fibrin, as supposed by that micogra- 



