126 CLINICAL BACTERIOLOGY AND 



at any moment, and as practitioners we, therefore, should 

 be on the lookout for such developments. 



In septic infection the bacteria gain entrance to the 

 blood-stream or lymphatics usually through a solution of 

 continuity of the skin or mucous membrane, and there 

 must be a tendency towards some defective bactericidal 

 power on the part of the patient, and probably phago- 

 cytosic inertia ; for, as one knows, so soon as a local centre 

 becomes infected, a ring of active cells is formed round 

 that area, thereby imprisoning the pathogenic elements. 



Should this ring remain intact, the most that will follow 

 will be osmosis of toxins through the barrier, which may get 

 into the circulation and set up septic intoxication, with 

 constitutional disturbance, if the toxin is virulent enouo-h 

 and sufficient has been absorbed. If, however, the wall 

 gives way through any defective effort of Nature on 

 the one hand, and extreme activity and virulence of the 

 bacteria on the other, septic infection follows. 



It is notorious the number of small punctured but deep- 

 seated wounds which act as a starting-point in the develop- 

 ment of a generalized septicasmia compared with superficial 

 and, maybe, more extensive lacerated wounds. This is 

 no doubt due to the fact that small punctured wounds 

 do not look serious in the mind of the layman, and 

 the owner or attendant may even ignore them altogether ; 

 whereas a superficial and an extensive wound looks ap- 

 palling to the lay observer, and he sets about to obtain 

 advice at once. And, again, a punctured wound is infected 

 at its blind end, where sunlight and ordinary dressings can 

 scarcely reach, while a proper temperature for bacterial 

 growth is always maintained, and the result is rapid bac- 

 terial development, with grave constitutional phenomena. 



The causative bacteria usually found in wound infection 

 are the streptococci and staphylococci ; and after castrations, 

 particularly in lambs, we have isolated a bacillus answering 

 the description of the B. coli communis — motile and Gram- 

 negative, etc. 



