REPARATOKY INFLAMMATION IN ARTERIES. 29 



distinctl}' seen in yoiingei- })reparations. e'. Elastic bands 

 from the lacerated intima, not so highly refractive or so free 

 from carmine-staining as the preceding. P. The cellular ele- 

 ments of plastic clot, wliich when separated by needles corre- 

 spond in outline and character with their description pre- 

 viously detailed. 



Kow we come to the consideration of the blood or fibrinous 

 clots. 



It has already been stated that Fig. 2, although drawn from 

 a preparation forty-eight hours old, lairl}- represents the strati- 

 fied appearance of all of these blood-clots. It can be seen by 

 a glance at the thrombus represented in Fig. 2, in longitudinal 

 section, that the clot is stratified, and that the strata are so 

 placed that, if judged from their position alone, one would 

 naturall3" conclude that the strata have been deposited at 

 four or more different epochs. It is not to be expected that 

 the blood caught by the ligature in the end of the stump of 

 the artery should, against experience, form at one time four 

 separate coagula, distinct and superimposed. The bui'den of 

 proof must rest upon him who will attempt to support the 

 assumption that the deposition of four distinct portions of the 

 blood-clot has been simultaneous. Moreover, the different 

 portions of this blood-clot, when studied closely and with a 

 high magnif3-ing power, bear internal evidence of a diversity 

 of age. They present ocular j)roof that they are of difterent 

 density and fii'mness; in other words, that the fibrin in the 

 lower has contracted more than it has in the higher portions. 

 The condition of the protoitlasmic elements which the different 

 portions contain also adds a confirmation to the inference that 

 the contents of the lower have been longer placed aside from 

 the circulation than have those of the higher. Considering all 

 these indications then, it would appear that there is reason for 

 the belief that the four ])orti()ns of the blood coagulum uiidi-r 

 discussion have been set aside from the circulation at four 



