CHAPTER X. 
SYMPTOMS OF VENOM POISONING IN MAN. 
The symptoms produced by the bites of venomous snakes vary according 
to the families to which they belong. Thus, the symptoms of cobra poison- 
ing differ from those of crotaline or viperine poisonings. Speaking in general, 
the local manifestation of poisoning is much more pronounced in the latter 
than in the former cases. ‘This rule is, however, not general, as some mem- 
bers of the colubrine snakes, for example the Australian genera, seem to 
stand nearer to the Crotalinz or Viperinz in their energetic attack on the local 
tissues. I do not intend here to discuss these differences and their causes, 
but will simply describe the symptoms observed by various authors in human 
cases bitten by various groups of venomous serpents. 
THE VIPERIDZ. 
CROTALUS POISONING IN MAN.’ 
Men are more frequently bitten than women. The situation of the wound 
is usually upon an extremity. The earliest symptom of the snake bite is 
the pain of the wound, although this is not reported in some cases. Ham- 
orrhage from the wound is very common, but may depend upon the size of 
the external opening of the wound inflicted by the fang, or perhaps, also, 
upon the character of the vessels accidentally penetrated by the fang. The 
primary local symptoms thus described increase progressively, so that within 
a period which varies extremely, the swelling and discoloration extend up 
the bitten limb, accompanied by pain of the most excruciating character. 
At this time, or after the first few minutes, the increase in the local symptom 
is probably due to the influence of the destructive action upon the tissue near 
the wound, to the irritation thus resulting, and to the indirect effect of venom 
upon local circulation. Thus the extremity becomes larger and more and 
more discolored until the skin shows every tint of an old bruise. Vesica- 
tions may appear on the surface, the pain lessens, the local temperature, early 
diminished, falls still lower, and unless the poison has ceased to act, gangrene 
ensues, and the tissue becomes necrotic. If, on the other hand, the poison is 
not present in a dose large enough to insure these effects, the swelling declines 
and the pain disappears with a celerity which the practitioner or reporter 
has assumed to be evidence of his own skill or of the utility of his therapeutic 
means, but which is an essential and most striking feature of crotalus poison- 
ing. The extent of damage brought about by the crotalus bite upon the local 
1 This account is derived from the work of Weir Mitchell. 
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