218 THE VENOM OF HELODERMA. 



The Agfa lecithin adsorbed approximately the same proportion of the venom, 

 while Kahlbaum's lecithin apparently adsorbed somewhat less than either of 

 the two first-mentioned preparations. This was due to the fact that emul- 

 sions prepared with Kahlbaum's lecithin were finer and that consequently the 

 supernatant fluid contained in this case a larger number of small particles of 

 lecithin, to which venom adhered. 



We find accordingly that the fluid obtained after filtration through a 

 Berkefeld filter was not more toxic in the case of Kahlbaum's than in the case 

 of Merck's lecithin; in most cases the lecithin adsorbed almost 70 per cent of 

 the venom and in a few experiments even more. 



All the mice injected with 2 c.c. of the washed and reemulsified residue 

 of lecithin died, irrespective of the kind of lecithin used; one mouse injected 

 with only 0.5 c.c. of the residue survived the injection. The amount of the 

 emulsion of the lecithin residue injected in this last-mentioned case should 

 have contained 3J lethal doses, provided all the venom had been adsorbed. 



We may conclude from these experiments that lecithin adsorbs a large 

 quantity of venom, but that the venom adsorbed exerts its toxic influence if 

 injected with the lecithin to which it adhered. 



The adsorptive power of a mixture of lecithin and cholesterin was also 

 tested. 0.07 mg. each of lecithin (Kahlbaum) and cholesterin (Merck) were 

 separately added to 7 c.c. of venom solution. Later a separation of the leci- 

 thin and cholesterin from this mixture was accomplished by means of a Berke- 

 feld filter. Three mice, injected with the clear filtrate, survived, while three 

 mice injected with the supernatant fluid obtained through centrifuging died as 

 soon as their controls. One mouse injected with the lecithin-cholesterin resi- 

 due died in a very short time. The addition of cholesterin to lecithin appears 

 to increase the amount of venom adsorbed. 



ADSORPTION OF VENOM BY THE ORGANS OF VARIOUS ANIMALS. 



We investigated the adsorptive powers of the organs of the heloderma, 

 turtle, frog, pigeon, guinea-pig, rabbit, and dog. Several organs were tested 

 in each animal; in every case the kidney and liver and in most cases the brain 

 also. In a few experiments some other parts were also used. As a rule, the 

 organs were tested immediately after the death of the animal, before impor- 

 tant autolytic processes could have taken place. The organs, cut into small 

 pieces, were rinsed with salt solution, in order to wash out the blood, and then 

 crushed in a mortar. 7 c.c. of venom solution were added to about 0.5 c.c. of 

 organ pulp. This mixture was rubbed in the mortar until an even suspension 

 of the organ pulp in the venom solution was obtained. 



The further steps were similar to those described above. The solid par- 

 ticles of the various organs were separated from the solution in most cases by 

 centrifugation and in a few cases by filtration through a Berkefeld filter. 



Heloderma brain was tested with both fresh and dry venom. With the 

 fresh venom all the animals injected with the supernatant fluid died: one 

 mouse injected with a volume corresponding to four lethal doses, one injected 



