REPARATORY INFLAMMATION IN ARTERIES. 37 



additi(Mial room it requires by slowly uplifting and pushing 

 before it the blood-clot, which had formed only loose lateral 

 attachments. Under the latter circumstance, I have never 

 found in any part of the blood coagulum the slightest tendency 

 to organization. In all the preparations of this date, the 

 plastic clot was found to be nearly double the size of the 

 average clot last described. The cells were nearly all spindle- 

 form, many of them possessing long processes. A number 

 of large stellate cells were also observed. A considerable 

 number of blood capillaries and vascular channels could now 

 be discerned. These were in connection above with the open 

 lumen of the artery; but in no place could an anastomosis 

 with tlie vaso vasorum be made out. In longitudinal sections, 

 the elastic layer of the intima could be distinctly traced with- 

 out the slightest breach or interruption from the top of the 

 section down to within an extremely short distance of the 

 point of ligation, and it appeared in its whole extent to be still 

 tough and resistant. Neither was the media vascularized ; the 

 vessels from the adventitia could not be traced inward beyond 

 the exterior lamellae of the muscular coat. 



The preparations which exhibited the above-described inva- 

 sion of the cracks and crevices of the blood-clot by granula- 

 tions springing from tlie plastic clot, demonstrated the fact that 

 these granulations also were composed of tissue identical in 

 structure with that of the formation from which they sprung. 

 They were not, however, vascularized. In cross-section of the 

 granulations it was impossible to distinguish any appearance 

 which could indicate tb'e occupation of their axis by a capillary. 



Fig. 6. Transverse section of the femoral artery of a dog, 

 eight days after ligature, highly magnified, a. Adventitia. m. 

 Media, e. Elastic layer of the intima, still sharply defined, 

 p. Granulations springing from the mass of cells developed 

 from tiie cellular elements of the intima; they consist of 

 spindle-cells, the direction of whose long axis in the main ob- 



