PATHOLOGY. 151 



Experiment 5. — Cat. Ether. Mesentery exposed and placed on the stage of 

 the microscope. The aqueous solution of venom was applied, and the experiment 

 watched under a magnifying power of 60 diameters. In thirty seconds minute 

 hemorrhagic points were noticed as in all the previous experiments first along 

 the sides of the smallest capillaries. It was also observed that the hemor- 

 rhages occurred first in those small capillaries which were in the neighborhood of 

 larger vessels. In vascular plexuses which started from the greater arteries the 

 hemorrhages appeared much sooner than in those which took their departure 

 from smaller arterioles. In each case, however, it was only the capillaries from 

 which the hemorrhages proceeded, the arteries and veins remaining intact. The 

 hemorrhages being seen to proceed from capillaries in the vicinity and along the 

 route of larger vessels, one may erroneously get the impression that it is the latter 

 from which the bleeding arises. No actual breech of continuity in the capillaries 

 was observed, and it appeared as though the blood filtered through the walls of 

 these minute channels. 



Experiment 6. — Kitten. Ether. Mesentery exposed in the usual manner. The 

 mesenteric vessels, both the main artery and the veins, were ligated near the root of 

 the mesenteric attachments. A salt solution stained by aniline blue was injected 

 into the vein. The venom was applied, and the field closely watched under the 

 microscope. No extravasation of the injected solution or of blood could be observed. 



Experiment 7. — Kitten. Ether. Vessels ligated and salt solution with aniline 

 injected as in previous experiment. Applied aqueous solution of the dry venom. 

 No extravasation of the colored liquid or blood observed. 



Experiment 8. — Kitten. Animal secured as before, but no salt solution injected. 

 Mesenteric veins and the artery ligated near root of mesentery. Solution of dried 

 venom applied. Hemorrhage as usual, but slow and scanty. 



Experiment 9. — Kitten. Ether. Animal fixed as in last experiment upon 

 microscopical stage. Fresh venom applied and watched for one-half hour. Hemor- 

 rhages were seen to develop more slowly. 



Experiment 10. — Kitten. Ether. Mesenteric vein and artery ligated as in pre- 

 ceding experiments. Fresh venom applied as before, and a marked delay in de- 

 velopment of hemorrhages again observed. 



Experiment 11. — Kitten. Ether. Mesenteric vessels tied not only at the root 

 of the mesentery, but also peripherally at the convex portion of the loop, thus 

 almost entirely cutting off the circulation. Fresh venom applied. Hemorrhages 

 were scarcely appreciable with the naked eye. 



Experiment 12. — Kitten. Ether. Mesenteric vessels tied at both root and peri- 

 phery of mesentery. Venom applied immediately. Hemorrhage hardly perceptible. 



The above experiments were subsequently repeated, especially those in reference 

 to the effects of the venom upon bloodvessels when blood had been substituted 

 by a 0.75 per cent, saline solution. These experiments, however, gave the same 

 results as those just described, and hence it is unnecessary to occupy space in multi- 

 plying similar records. Yet some studies in the same direction have been left 

 undone. It might be desirable to elaborate the methods of experimentation, e. g., 

 by application of artificial blood pressure, etc. In all the experiments above quoted. 



