CERTAIN DERIVATIVES OF THE PROTEIDS. 297 



immediate action of the peptones and proteoses on the neuro- 

 muscular apparatus of the vessels, while the latter phenomenon 

 stands in no causal relation to the arterial fall. Thus we have 

 observed in many experiments an entire absence of diminished 

 coagulability, notwithstanding a pronounced fall in pressure. 

 (Cf. experiments on peptone, gelatoses, and gelatin-peptone.)* 

 Ledoux f has arrived at a similar conclusion, and Thompson J 

 has. found that a dose of Witte's "pepton " entirely insufficient 

 to retard coagulation may still lower blood-pressure, as 

 Fano had previously found to be the case in general with 

 acid-albumin. Finally, Dastre and Floresco || have quite re- 

 cently demonstrated that intravenous injections of bile may 

 entirely prevent the action of proteoses on blood coagulation 

 without interfering with the fall of arterial pressure. 



Immunity. Since the experiments of Schmidt-Miilheim IT 

 and more particularly of Fano,** it has been known that an 

 intravenous injection of so-called " peptone " (propeptones) 

 which suffices to render the blood non-coagulable for a time 

 apparently confers upon the animal a degree of immunity 

 against subsequent injections of the " peptone." For example, 

 if after the return of normal coagulability to the blood a 

 second injection of albumoses is made, the latter now fails to 

 deprive the blood of its ordinary extra vascular clotting power. 

 Furthermore, Fano demonstrated that an injection of tryptone 

 (antipeptone from pancreatic digestion) which is without 

 influence on the coagulation of the blood, nevertheless may 

 render the dog immune against subsequent injections of albu- 

 mose-peptone. Spiro and Ellinger ff have likewise found that 

 injection of anti-peptone has an antagonistic influence on the 

 action of Witte's " pepton " on blood coagulation. Grosjean JJ 



* See also Arthus and Huber, loc. cit., p. 861. 

 t Ledoux, Archives de biologie, 1896, xiv, p. 63. 

 t Thompson, Journal of Physiology, 1896, xx. 

 Fano, Archiv f. Physiol., 1881, p. 277. 



|| Dastre and Floresco, Comptes rendus de la soc. de biologie, 1898, p. 468. 

 1 Schmidt-Mulheim, Archiv f. Physiol., 1880, p. 30. 

 ** Fano, Archives ital. de biologie, 1882, ii, p. 146. 

 tt Spiro and Ellinger, Zeitschr. f. physiol. Chem., 1897, xxiii, p. 137. 

 Jt Grosjean, Archives de biologie, 1892, xii. 



