490 



Dr. L. Rogers. On the Physiological 



[Mar. 31, 



having no hemolytic action, for the solutions employed for the small 

 animals experimented on were 1 in 10,000 or less. If we work out 

 the amount of poison required to dissolve a certain amount of the 

 blood of a pigeon, for example, we find that it takes about 200 times 

 a fatal dose to dissolve 1 /2000th part of the bird's blood in twenty- 

 four hours, calculating this fluid to be one-thirteenth of its body 

 weight. It is obvious, then, that ordinary fatal doses of the poison of 

 the Hydrophida? can have no appreciable hemolytic effect, and that 

 death cannot be attributed, even in a partial degree, to its action on 

 the blood of the animal killed by it. This can also be demonstrated 

 by another method of experiment, namely, by counting the number of 

 the red corpuscles before the administration of the fatal dose of 

 the poison, and again immediately after death. This I have done 

 several times, with the result of showing that no dissolution of the red 

 corpuscles resulted from the action of a lethal dose of the Enhydrina 

 poison. For example, a fowl's blood was counted, and 3,190,000 red 

 corpuscles per cubic millimetre were found. A lethal dose of Enhy- 

 drina poison was then injected subcutaneously, which proved fatal in 

 just one hour, when the blood count showed 3,120,000 red corpuscles 

 in the same quantity of blood. 



Next we have to deal with the action of the poison on the coagul- 

 ability of the blood. In the case of Cobra venom marked changes are 

 produced, as shown by D. D. Cunningham, and this point has recently 

 been studied by Lamb. The virus has the action of reducing or 

 totally destroying the clotting power of the blood when mixed with it 

 in small quantities. I have made a few observations on this point 

 with the following results. Wright's tubes were used, the solution of 

 the poison being first drawn up into them, and then an equal quantity 

 of the blood drawn up and quickly mixed with the venom solution in the 

 mixing chamber, and blown down into the tube again, and the condi- 

 tions as regards clotting examined in a series of such tubes at given 

 intervals. The clotting time, when mixed with an equal quantity of 

 the normal salt solution (in which the venom w T as also dissolved) of a 

 rabbit, having first been found to be three minutes, those of different 

 strengths of Cobra venom in normal salt solution were found to be as 

 follows : when a l-in-10,000 solution was added the coagulation 

 time was seven and a half minutes; with l-in-1000 solution it was 

 twenty minutes, and with a l-in-200 one the blood was still quite 

 fluid after twenty-four hours, its coagulability having been completely 

 destroyed. On testing the effect of the poison of the Enhydrina in a 

 similar manner it was found that a l-in-1000 solution had no effect in 

 reducing the coagulability of the blood, which still clotted solid 

 in three minutes ; when a l-in-200 solution was added the blood still 

 clotted in five minutes, showing only a slightly reduced time with the 

 same strength, which in the case of Cobra venom had completely 



