66 THE VENOM OF HELODERMA. 



a hemorrhage in the posterior portion of the orbital space which gradually 

 increases. The eye-ball is thus pressed forward and exophthalmus develops. 

 In some unexplained manner the cornea becomes opaque. The blood works 

 its way forward in the periocular tissue until it appears under the conjunctiva 

 and this may at times, as a result of either the internal pressure or the trauma 

 of the conjunctiva, produce conjunctival oozing. 



The cause for the primary hemorrhage in the posterior portion of the 

 orbital space is not clear. We have no evidence which would point to any 

 vascular lesions causing a greater permeability of the vessels for the red blood- 

 cells. The probable explanation must, therefore, be sought in an increase of 

 the intravascular pressure within the vessels of the brain and orbit sufficiently 

 great to cause a rupture of the thin and rather poorly supported vessels of the 

 orbit. 



A somewhat similar condition has been noted by Emmert* in mice which 

 were injected with adrenalin. He found that when adrenalin was injected sub- 

 cutaneously into mice, the eye-ball protruded and the cornea became opaque, 

 but this author makes no mention of any hemorrhage. He also observed 

 that the lens was pressed forward. 



ANATOMICAL LESIONS PRODUCED BY INJECTION OF VENOM. 



The most conspicuous and common of the macroscopic changes to be seen 

 after death are found in the alimentary canal. These are particular^ marked 

 if some hours have elapsed between the injection of venom and the animal's 

 death. The serous layer of the intestines and stomach is usually markedly 

 congested. The intestines are much dilated with fluid and gas. In guinea- 

 pigs and rabbits the only mammals investigated with reference to this point 

 the mucous layer of the stomach was congested and showed small hemorrhages 

 and areas of self-digestion. To determine beyond question that these changes 

 were produced by the venom we made the following experiments : The abdom- 

 inal cavity of four guinea-pigs was opened and the condition of the intestines 

 noted. The abdominal wall was then sewed up and three animals were in- 

 jected subcutaneously with varying doses of venom and one with the same 

 volume of physiological salt solution. Immediately after death the intestines 

 of the animals injected with venom were found to contain much more fluid and 

 gas than they had contained before injection and also to show the other symp- 

 toms previously mentioned. The animal which had been injected with salt 

 solution was killed and found to have undergone no evident alteration of the 

 alimentary canal. Two control guinea-pigs belonging to the same lot were 

 killed and likewise showed no abnormalities of stomach or intestine. 



Inasmuch as certain of the snake venoms are perhaps excreted through 

 the gastric mucous membrane, it might be thought that the post-mortem 

 changes observed in this organ were due directly to a digestive action of the 

 heloderma venom. In order to see whether similar changes might not be pro- 

 duced by other methods of slow poisoning, we killed guinea-pigs by injecting 

 sublethal doses of potassium cyanide and of resorcin, repeating the injections 



*Emmert, Virchow's Archiv, 1908, 194, 114. 



