258 C. J. MARTIN. 
of the respirations, followed by a decrease in both. These 
venoms affected the respiratory rhythm to a much greater extent 
than the respiratory excursus in the majority of cases. 
Feoktistow' found a tremendous increase in respiration, followed 
by asphyxia, after intravenous injection of the poisons of Crotalus — 
and Vipera berus. His conclusions as to the explanation of these 
phenomena are not very valuable, as he was undoubtedly dealing 
with cases of intravascular clotting, although he was quite — 
unaware of such a contingency. He does not appear to have 
made any observation on the respiration after the subcutaneous 
injection of the poisons. 
After injection of Pseudechis venom the respiratory movements 
become less and less, and ultimately cease. As I have shown 
that this action of the nervous system may occur independently 
of any effect on the circulation, and also that the venom has n0 
effect on motor nerves, or their endings in muscle, it must exert 
its action directly upon the respiratory centre in the medulla. 
Its action in this respect is best seen when the venom is sub- 
cutaneously introduced in rabbits. Under these conditions, the : 
paralysis is often preceded by a period in which the respirations: 
are increased both in number and in extent. The period 
increased respiratory activity is much more strongly manifested 
in some experiments than in others, and is indeed not infrequently — 
entirely absent. 
Both Brunton and Fayrer? and Mitchell and Reichert’ state 
that the primary acceleration of the respirations was absent after 
cutting the vagi, and the first mentioned observers accordingly 4 
attribute this increase in respiratory rhythm to the operation of : 
the poison upon the peripheral terminations of the vagi in the 
lungs. My results with Pseudechis poison are however not 12 
accordance with such a view. The primary acceleration is often 
absent both in animals with severed, and in those with intact vag, 
but occurs with about equal frequency under both conditions. In 
mes 
1 Loe cit. 2 Loc. cit. 3 Loc. cit. 
i 
