INTRAVASCULAR COAGULATION. 311 



blood. According to WOOLDRIDGE it can generally be maintained that 

 after a short stage of accelerated coagulability, which may lead to a 

 total or partial intravascular coagulation, a second stage of a diminished 

 or even arrested coagulability of the blood follows. The first stage is 

 designated (WOOLDRIDGE) as the positive and the other as the negative 

 phase of coagulation. These statements have been confirmed by several 

 investigators. 



There is no doubt that the positive phase is brought about by an 

 abundant introduction of thrombin, or by a rapid and abundant formation 

 of the same. The explanation of the production of the negative phase, 

 which can easily be brought about by pepsin proteoses, by various bodies 

 such as extracts of crabs' muscles and other organs, eel -serum, enzymes, 

 bacterial toxines, certain snake-poisons, etc., has been attempted in dif- 

 ferent ways. The best studied is the action of proteoses, but no conclusive 

 results have been obtained thus far. The assertion of PICK and SPTRO 

 that the action of the proteoses does not depend upon the proteoses 

 themselves, but upon a contaminating substance, the protozym, is 

 claimed to be incorrect by UNDERBILL, while the recent investigations 

 of POPIELSKI indicate that this is correct. The bodies retarding coagu- 

 lation obtained by CONRADI 1 in autolysis, which are probably antithrom- 

 bins, seem to act in a different way from the proteoses, and cannot for 

 the present be made use of in explaining this question. 



There are a large number of researches on the action of proteoses 

 and of other retarding substances by different investigators, such as 

 GROSJEAN, LEDOUX, CONTEJEAN, DASTRE, FLORESCO, ATHANASIU, CAR- 

 WALLO, GLEY, PACHON and GLEY, SPIRO and ELLINGER, FULD and SPIRO, 

 MORAWITZ and NOLF, but those of DELEZENNE 2 are of the greatest impor- 

 tance. We can say with certainty that the action is indirect and that 

 the liver is important for the process. The non-coagulability of " pep- 

 tone-blood " seems to be due to several reasons, but it has not been 

 thoroughly explained. On the one hand such blood contains an anti- 

 thrombin and on the other it seems as if the formation of thrombin 

 is not sufficient, although the plasma contains the necessary conditions 

 for the thrombin formation, as it coagulates as a rule on dilution with 



1 Pick and Spiro, Zeitschr. f. physiol. Chem., 31; Underbill, Amer. Journ. of Physiol., 

 9; Popielski, Arch. f. expt. Path. u. Pharm. Suppl., 1908, Schmiedeberg's Festschrift; 

 Conradi, Hofmeister's Beitrage, 1. 



2 Grosjean, Travaux du lahoratoire de L. Fredericq, 4, Liege, 1892; Ledoux, ibid., 

 5, 1896; Nolf, Bull. 1'Acad. roy. de Belgique, 1902 and 1905, and Biochem. Centralbl., 3; 

 Spiro and Ellinger, Zeitschr. f. physiol. Chem., 23; Fuld and Spiro, 1. c.; Morawitz, 

 1. c. The works of the above-mentioned French investigators can be found in Compt. 

 rend. soc. biol., 46, 47, 48, 50, and 51, and Arch. d. Physiol. (5), 7, 8, 9, and 10; see 

 -also especially Delezenne, Arch. d. Physiol. (5), 10; Compt. rend. soc. biol., 51, and 

 Compt. rend., 130. 



