PHYSIOLOGICAL ACTION OF VENOM OF BLACK SNAKE. 153 
Weir Mitchell and Reichert! found that in a drop of mammalian 
blood mixed with “(a minute quantity ” of crotalus venom the 
activity of the leucocytes absolutely ceased. The red corpuscles 
lost their biconcave form and became spherical and sticky, so that 
they adherred together in strings. Ultimately the haemoglobin 
_ dissolved out and they became invisible. When pigeon’s blood 
was subjected to the action of the venom, the nuclei of the cor- 
puscles appeared to undergo a rapid necrotic change, which finally 
gave rise to a granular albuminoid material which was seen float- 
ing in large quantities between the corpuscles. 
Feoktistow? who worked with the venoms of Crotalus and Pelias 
berus found that 2% solutions of these venoms produced dissolu- 
tion of the corpuscles after 18 — 24 hours. 
The first animal the blood of which I submitted to the action of 
Pseudechis venom was the frog. A drop of frog’s blood was mixed 
with an equal bulk of a ‘7% solution of NaCl containing ‘19/ of 
venom. The mixture was made on a slide, and speedily covered 
with a cover glass and the edges smeared with oil to prevent con- 
centration of the salt solution by evaporation. Within a few 
moments a disintegration of the red cells occurred. They lost 
their shape, their nuclei became apparent, and the haemoglobin 
dissolved out ; afterwards they appeared larger and circular, and 
me more and more indistinct, until finally nothing could be 
_ Seen of them, but shrivelled granular nuclei. These shrivelled 
_ huelei soon began to swell, the granules became less distinguish- 
able and eventually disappeared. The disappearance of the red 
oe Was 80 complete that at the end of fifteen minutes there was 
nothing except the slight colouration of the field, to distinguish 
7 the preparation from one of lymph. 
- The action on the white cells was much slower. For the first 
minutes I could discover no change in them, but they 
* Loe. cit. p. 143. | 
: “ Ueber die Wirkung des Schlangengiftes auf den thierischen 
Série pen Mémoires de l’Acad. imp. d. Se. de S. Pétersbourg, VII 
Rs. > Tome XXXVL, .) . 
