WOUNDS 413 



the retraction of the parts generally leaves a large exposed 

 surface. 



Contused Wounds are those in which, besides a cut, con- 

 siderable bruising of surrounding parts results from in- 

 jury with a blunt instrument, or contact with a hard, irre- 

 gular surface. The bruise renders the case much more 

 complex than it otherwise would be, for, besides simple 

 repair of the cut, much tissue must be removed or re- 

 stored. A similar condition without the cut is termed a 

 contusion, and is less serious, as reparative changes take 

 place most readily without access of the air. The blood 

 thrown out in this latter case forms a hamatoma or blood 

 tumour. The clot which is formed does not undergo 

 organisation, at any rate as a rule, but becomes slowly 

 absorbed. 



Poisoned Wounds show a tendency to gangrenous 

 results, and heal very badly ; they are not frequent in 

 cattle. 



Gunshot Wounds require no detailed notice from us. 

 The methods by which repair is brought about are as fol- 

 lows : — Repair by growth, where no reparative processes 

 are set up, but the injury has not been sufficient to dis- 

 arrange the relations between the cells, so in process of 

 time the space left is filled up ; ^primary union, where the 

 parts, being brought together at once after the wound, 

 become united without any mark of injury being left ; the 

 two surfaces are so grafted together that the necessary in- 

 fluences of neighbouring tissues may be exerted between 

 them ; jprimary adhesion occurs when two exposed surfaces 

 are brought together some little time after the injury, and 

 maintained in apposition, union being the result of the ad- 

 hesive influence of lymphy material on each surface ; 

 repair by granulation is the most frequent method ; in this 

 the exposed surface, after haemorrhage has ceased, seems 

 to be covered with a glaze, which is the adhesive material, 

 simply thrown-out by the blood-vessels; this becomes 

 covered with little, highly vascular, minute projections, 

 resembling papillae in their figure ; also pus is formed at 

 about this time. The wound is gradually closed by the 



