16 THE TONER LECTURES. 



muscular tunic " It is then by raeclianical penetration, and 

 tlianlis to tlie thinness o^ *-he venous walls, that the particles 

 of vermilion have ti'avelleci as far as the clot." Durante 

 thinks the orio'in of the formative cells in the single lioature 



O DO 



is to be found in the endoth*^lium, or the ramilied cells of the 

 internal membrane. 



Baumgarten (Centralblatt fiir die Medicinischen Wissen- 

 schaften, No. 34, 1876) publishes the very latest investigation 

 upon the healing of arteries. He sums up the substance of 

 his researches as follows: — 



1st. The so-called organization of red thrombi is due to two 

 distinct processes : first, a proliferation of the arterial endo- 

 thelium; and, second, an invasion from without of connective 

 tissue elements from which the new bloodvessels are solely 

 formed. 



2d. The part played by the clot in the organization is nil ; 

 an occasional fragment of encapsuled pigment is the onl^^ rem- 

 nant it leaves. 



A. Pitres (Recherches experimentales sur le mode de forma- 

 tion et sur la structure des caillots qui determincnt I'hemostasie. 

 Arch, de Phys. Nov. et Path., 18*76) affirms that lisemostasis is 

 usually spontaneously secured by a clot composed of three 

 distinct portions : an external part, which is a simple blood 

 coagulum, and which is only an accessor}' ; a middle i)art, 

 which 'is lodged in the wound, or lumen of the vessel, which is 

 the most constant and active agent of spontaneous hoemos- 

 tasis, and which consists almost exclusively of white blood- 

 corpuscles ; and an interior clot, which has merely an acci- 

 dental office, and which has a complicated constitution. 



SUMMARY OF PREVALENT OPINIONS. 



We have seen that notwithstanding the apparent confidence 

 and sometimes even dogmatism with which the leading pathol- 

 ogists have published opinions and advocated theories con- 



