46 THE TOXER LECTURES. 



piessure is very similar to that which secures the obliteration 

 of the ligated artery. The sections examined show that the 

 blood coagula in all have been fashioned in accordance with 

 the same general law previously enunciated for ligature, and 

 that there has been a similar although very much less marked 

 increase in the cells of the intima at the point of greatest irri- 

 tation, which in the third method is at the locus of the needle. 



Fig. 10 represents a thrombus after acupresaure (third 

 method), 36 hours old. Low power. 



a. Adventitia. m. Media, n. Position of needle. 79. Plastic 

 clot at the bottom, d. Stratified clot above, l. Portion of 

 lumen now free ; when the section was made this was occupied 

 by a recent unstratified or homogeneous blood-clot which 

 fell out during handling. 



In the preparations obtained by acutorsion (or the fourth 

 method), the chief difference from the preceding was that the 

 processes were more active. In all the preparations of this 

 series the plastic clot seemed to be the sole organizing agent, 

 the blood coagula to be inert or passive. 



Fifth Series. — The fifth and last series consisted of a few 

 preparations obtained by compressing, between the arms of 

 serre-fines, the femoral and common carotid arteries of good 

 strong rats — the pressure being continued from two to four 

 hours. In some of these preparations there was evidence that 

 the channel of the artery had been restored soon after removal 

 of the pressure. In some, however, the lumen of the vessel 

 remained permanently occluded. In the latter the surfaces of 

 the intima brought into contact by the serre-fines remained 

 adherent, and a blood and plastic coagulum similar to those 

 seen after acupressure by the third method were observed. 

 The plastic clot here also played the same role as in the 

 former series, but the inflammatory process, as might have 

 been expected, was even less advanced than in the case of 

 acupressure. 



