( 642 ) 
the olfactory mucous membrane, for I found the same reaction with 
one of the dogs, narcotized through the trachea after tracheotomy. 
This occurred, when I wanted to stimulate the fila olfactoria by 
means of electricity and therefore would not paralyze them before- 
hand by chloroformvapours. This violent reaction, when found with 
dogs which had been first tied, may cause the dogs to succumb; if 
however, we leave a possibility of free movement, which is best | 
done by tying the dogs in a bag leaving only the head and the legs 
free, and the bag with the dog suspended in the air, the asphyxia 
is generally not found, and the further narcosis remains very | 
calm and regular. The chloroform was administered by means of 
CURSCHMANN’s inhalator. 
The narcosis being deep enough, tracheotomy was performed and 
the chloroform was administered through the tracheal canula. 
The registration took place with the pneumograph of MAReY. 
The sensible nerves were stimulated with a moderately strong in- 
duction current. Generally, differences in the strength of the current | 
had little influence, except that a certain minimum had to be 
exceeded. : 
Under these circumstances, i which the results show much 
uniformity and constancy, it appeared that the stimulation of those 
periferie nerves, which are exclusively composed of sympathie 
nerve-fibres or contain many of them, brought about an arrest 
of the respiration and generally, as has been found already by 
Harney and HAMBURGER, in its expiratory position. So do the 
N.splanchnicus and the N. vago-sympathicus. I succeeded sometimes 
by mechanic stimulation of the N. splanchnicus (by traction of the 
entrails) in arresting the respiration for 65 seconds, as long as the 
stimulation lasted, while before and after the stimulation the respi- 
ration was perfectly regular. By electrical stimulation of the N. | 
splanchnicus the same result was obtained. This proves that no 
centre has been disturbed by shock. The same thing is seen when 
the N. vago-sympathicus is stimulated (see fig. I—-LY). 
The excitation of the N. laryngeus superior gives also an arrest 
in the expiratory position, but has generally, in the same way as 
the sensible branches of the N. trigeminus, an after-effect of long 
duration. Some time passes before the dog breathes again calmly, 
and there is a tendency to get out of the narcosis. If the narcosis 
is very deep the effect is simple retardation (see fig. V). 
That of the N. glossopharyngeus always gives a deep inspiratory 
position, as is never reached in simple breathing, but only with deep 
sighs. Strong currents bring about a forced deep inspiration lasting 
