REPARATORY INFLAMMATION IN ARTERIES. 31 



of the Stratum was in contact with that of the coil next aLove 

 or below — adjacent coils being bound together by intervening 

 bands of fibrin. The meshes formed by these cross-bands also 

 were filled with numbers of white blood-cells, scarcely any red 

 cues. 



What is the significance of this interesting serpentine lamel- 

 lation of each of those three lower portions of the blood-clot? 



Before proceeding to the solution of this question, let it be 

 again distinctly understood that in the examination of this clot 

 of 48 hours Me arc not directing our attention to an exceptional 

 formation, but, so far as my observation goes, to a tyi)ical 

 blood-coagulum, such as usually forms when conditions are 

 favorable to healing in arteries after ligature. The only excej)- 

 tions as yet found have been limited to cases where it was 

 impossible to discover the slightest sign of an attempt at heal- 

 ing, or where the first collateral branch happened to be given 

 off immediately above the ligature, in which case there gener- 

 allj' was no blood-cl«)t at all. 



Let lis recur now to the serpentine lamellation of these por- 

 tions of the fibrinous clot. 



Possibl}' the following observations made upon the large ves- 

 sels of the mesentery and tongue of the living frog may con- 

 tribute something toward an explanation. 



The abdomen of a curarized frog was opened at a convenient 

 point, and a loop of intestine was withdrawn. The latter was 

 so placed as to bring to view in the field of the microscoije one 

 of the mesenteric arteries. B}- carefully stretching the exposed 

 loop the velocity of the circulation was easily reduced lo a con- 

 venient slowness. The most important fact obtained b}^ this 

 experiment may be best stated b}' detailing that portion of the 

 observation which rcijates to it. By stretching the intestinal 

 loop not only could the l)lood-current l)e slowed, but, by the 

 employment of a little more force, it would be arrested entirely, 

 and b}^ continuing tiie strain a few moments it could be even 



