SNAKE-POlSON AND iTS ACTION. 25 



be kept in mind by those who inject ammonia in 

 serious snakebite cases, and it probably applies like- 

 wise to the excessive use of alcohol. 



This leads the writer on to the discussion of this 

 singular hsemorrhagic process principally characteristic 

 of viperine poisoning, and only very exceptionally 

 produced by the poison of colubrines. It is among 

 the symptoms of snakebite poisoning one of the most 

 interesting ones, but also one most difficult of explan- 

 ation. There can be no doubt that it is produced by 

 vaso-motor paresis and paral^'^sis. We further know 

 that it is preceded by dilatation of the capillaries and 

 small veins, and that it is effected principally through 

 the process known as diapedesis, or the passage of 

 both red and white corpuscles with plasma through 

 the unruptured capillary membrane, and even the thin 

 one of small veins, which is nearly of the same struc- 

 ture, being composed of endothelial cells united by 

 cement. This membrane possesses a certain degree of 

 porosity, which is probably increased by dilatation. In 

 the absence of plain muscular fibres contraction and 

 dilatation of the capillaries can only be effected by a 

 corresponding contraction and expansion of the nuclei 

 of the endothelial cells. As fibrils derived from non- 

 meduUated nerves terminate in small end-butts in 

 connection with the capillary membrane, we may 

 assume that the nuclei of the endothelial cells are 

 under the sway of vaso-motor nerve currents, that 

 weak ones will expand, strong ones contract them. 

 We may further assume that the red and white cor- 



