148 THE VENOMS OF CERTAIN THANATOTHIDE^. 



chyma, filling also all of the air vesicles. There were extensive snh-pleural ecchy- 

 moses, both parietal and visceral, as well as sub-pericardial ecchymoses. Under the 

 microscope with high amplication sections of the lung tissue showed a peculiar 

 clogging, fusion, and ductility of the red blood-corpuscles not unlike that which 

 follows the application of fresh venom to the blood. 



This appearance is, however, not uniform, as in many places the corpuscles are 

 merely spheroidal, or have undergone a granular disintegration. The bloodvessels 

 are all highly congested, the air vesicles seem to be distended by extravasated blood. 

 The micrococci introduced with the venom appear to have rapidly multiplied, 

 numerous masses being seen in the air vesicles and in the more necrosed parts of 

 the lung tissue. In general the tissue is deeply stained by the coloring matter of 

 the blood. 



Brain and Medulla Ol>longata. If a minute quantity of venom was successfully 

 injected directly into the cranial cavity of a pigeon, the animal fell immediately and 

 expired in a few minutes. The pia mater was preeminently the seat of hemor- 

 rhages, and blood was also seen to fill the peri-vascular spaces of many of the cere- 

 bral vessels. The cerebral tissue, and particularly the nerve elements, showed a 

 granular change analogous to that observed in muscular tissue, and similar appear- 

 ances were noted from the effects of the venom upon the medulla oblongata and 

 spinal cord. Where animals were poisoned by introducing the venom subcuta- 

 neously into some other part of the body, minute capillary hemorrhages were 

 also observed in the membranes of the brain, and in two instances ecchymoses 

 were noted in the substance of the medulla oblongata, although as a rule only 

 intense congestion of its vessels was seen. .The bloodvessels were so much 

 distended with blood as to be double or even triple their normal calibre, fully 

 obliterating the perivascular spaces and unquestionably exerting much pressure 

 upon the surrounding nerve elements. 



Effects of (lie Venom when applied to Uninjured Mucous Menibranes, and upon the 



Cornea. 



The following experiments were made : 



Experiment. Adult albino rabbit, etherized. A drop of an aqueous solution of 

 the dried venom Crotalus adamanteus was dropped on the cornea and conjunctiva 

 of the left eye. In a few minutes the conjunctiva became ecchymosed and cede- 

 matous to such an extent as to close the eyelids. Animal died in five hours. After 

 death the conjunctiva and eyelids were seen to be soaked with extravasated blood, 

 while the cornea remained perfectly transparent and colorless, showing no trace of 

 inflammatory change when removed and examined under the microscope. 



Post-mortem examination showed extensive sub-pleural, sub-peritoneal, and slight 

 sub-arachnoid ecchymoses. 



Experiment. Young kitten, etherized. A drop of fresh venom was placed on 

 the cornea. Results, similar to those of foregoing experiments, the cornea remain- 

 ing transparent, but exhibiting a certain roughness upon the surface, which under 

 the microscope proved to be due to slight desquamation of the epithelium. 



