224 



BACTERIOLOGY. 



but, instead, the needle is introduced into the subcuta- 

 neous tissues along the edge of the incision. In this case 

 they are to pass into the abdominal cavity and out again, 

 entering at one side of the line of incision and leaving 

 at the other, as indicated by the solid and dotted lines 

 in Fig. 46. (The figure indicates the primary opening 

 through the skin. The longitudinal dotted line shows 

 the opening to be made into the abdomen ; the transverse 

 dotted lines, with their loose ends, represent the sutures 

 as placed in position before the abdomen is opened ; it 

 will be seen that these sutures in all cases pass through 

 the subcutaneous tissues only and do not penetrate the 



skin proper.) 



FIG. 46. 



Diagram of skin incision and sutures in laparotomy on animals. 



The opening through the remaining layers may now 

 be completed ; the bit of tissue is deposited in the peri- 

 toneal cavity, under precautions that will exclude all 

 else, the edges of the wound drawn evenly and gently 

 together by tying the sutures, and the lines of incision 

 dressed with collodion. It should be needless to say 

 that this operation must be conducted under the strictest 



