Scientific Proceedings. 



(213) 43 



birds and in mammalian* blood outside of the body under conditions 

 that entirely exclude coagulation, as after phosphorus poisoning, 

 also in hirudin blood, and in bird's blood collected according to 

 Delezenne's method. 



In order to clear up these discrepancies the author carried out 

 experiments on a relatively large number of animals. In arthro- 

 pods, and especially in Limulus, he found in various experiments 

 that the collection of blood cells around the foreign body, which 

 leads ultimately to the formation of a hyaline thrombus, was due to 

 a primary process of agglutination and that coagulation processes 

 could be entirely excluded. The same applies to the extravascular 

 coagulation of Limulus blood. 



In birds and dogs the blood was made temporarily noncoagu- 

 lable by injecting hirudin or peptone. In a number of experi- 

 ments not only was the increase in the coagulation time of the blood 

 in the injected animal observed, but the blood was also tested in 

 regard to its reaction toward the tissue coagulins which accelerate 

 the coagulation of the blood. The blood vessels were injured in 

 different ways and were later examined microscopically. In the 

 large majority of cases serial sections were made of each injured 

 blood-vessel. Seven geese were used for hirudin injections, includ- 

 ing the controls ; 38 blood-vessels of 19 dogs were examined after 

 hirudin injections (controls included) ; 2 5 blood-vessels of 1 2 dogs 

 were examined after peptone injections (controls included). 



The following conclusions may be drawn from the results 

 obtained : 



In invertebrates as well as vertebrates an agglutination of blood- 

 cells or of blood-plates may take place around foreign bodies or at 

 the place of injury of the vessel-wall. This agglutination can be 

 present without the occurrence of any simultaneous or previous 

 formation of fibrin. The formation of such agglutination thrombi 

 corresponds to the clumping of the same cellular elements outside 

 of the body, where the agglutination can take place without being 

 accompanied by any coagulative process. 



In birds the injection of hirudin does not materially alter the 

 readiness with which a thrombus is formed. In dogs, on the other 

 hand, it is very probable that injections of hirudin delay or may 

 sometimes prevent the formation of agglutination thrombi. The 



