218 BAOTEBIOLOOY. 



Inoculation into the Lymphatic Circulation. 

 — Fluid cultures or suspensions of bacteria may be in- 

 jected into the lymphatics by way of the testicles. The 

 operation is a simple one. One simply plunges the 

 point of the hypodermic needle directly into the sub- 

 stance of the testicle and then injects the amount desired. 



Injections made in this manner are sometimes fol- 

 lowed by interesting pathological lesions of the lym- 

 phatic apparatus of the abdomen. 



inoculation into the great serous cavities. 



Inoculation into the peritoneum presents no difficulties 

 if fluids are to be introduced. In this case one makes, 

 with a pair of sterilized scissors, a small nick through 

 the skin down to the underlying fasciae, and, taking up a 

 fold of the abdominal wall between the fingers, plunges 

 the hypodermic needle through the opening just made 

 directly into the peritoneal cavity. There is no fear of 

 penetrating the intestines or other internal viscera if 

 the puncture be made along the median line at about 

 midway between the end of the sternum and the sym- 

 physis pubis. Though this may seem a rude method, 

 it is, nevertheless, the rarest of accidents to find that 

 the intestines have been penetrated. The object of the 

 primary incision is to lessen the chances of contaminat- 

 ing the inoculation by bacteria located in the skin, some 

 of which would adhere to the needle if it were plunged 

 directly through the skin, and might complicate the re- 

 sults. 



If solid substances, bits of tissue, etc., are to be intro- 

 duced into the peritoneum, it becomes necessary to con- 

 duct the operation upon the lines of a laparotomy. 



