Franz, T%vo hUematwual Congresses. 93 



effect of the salts on the colloid protoplasm. Later experiments of the effects of 

 salts on albumen and lecithin have shown that there is a close relation between 

 the effects on colloid and on the excitability. The excitability alterations pro- 

 duced by salts resemble corresponnding (i. e., reversible) electromotor phenom- 

 ena, and a connection can be shown between the alterations of excitability and 

 the condition of the colloid protoplasm. The conclusion that the reader further 

 drew from the results of his experiments is that normal production of excitation 

 by the usual electrical means is accompanied by alterations in the condition 

 (composition) of the colloid. This it will be noted is the same conclusion that 

 was reached by Macdonald in the paper mentioned above. This view of the nature 

 of excitation is corroborated by the fact that the current of rest produced by the 

 action of salts is, like the action current, retarded by various narcotics. According 

 to the view of excitation and the action of various narcotics the nature of narcosis 

 must be or must depend upon some sort of retardation of the colloid process nor- 

 mally accompanying excitation. 



Dr. N. A. Barbieri (Paris), H, denied that there is any regeneration in nerve 

 fibers, after they have been sectioned. His paper contained statements not in 

 accord with the experience of the return of function in man and other animals, and 

 it was difficult to get the author's point of view. The abstract of his paper, "Cycle 

 d'evolution des nerfs sectionnes" gives the following conclusions: There exists no 

 autoregeneration of nerves. In strictly physiological evolution the peripheral end 

 of a sectioned nerve remains inexcitable and always degenerates; the central end 

 does not regenerate, but remains excitable and its structure remains normal. If 

 suppuration exists the central end of the nerve also undergoes retrograde degenera- 

 tion. If there be no regeneration of a divided nerve it is difficult, or perhaps 

 impossible, to explain how the animal recovers the motor and sensory functions after 

 an interval of time. The experimental evidence adduced by Barbieri in support 

 of his conclusions is not of the best, I believe, for he waited only three months for 

 the regeneration of the vagus nerve. Had he extended his experiments over a 

 longer period of time he would doubtless have been compelled to conclude that 

 regeneration is the rule in respect to the peripheral nerves. 



Certain nerves and parts of nerves have been long known to have an inhibitory 

 function. Flxamples of this are the vagus and the so-called vasodilator nerves. 

 The inhibitory function for the muscular nerves was shown by Professor NicoL- 

 AIDES (Athens), H, by demonstrations on the frog. The nerve fibers supplying 

 the gastrocnemius muscle of the frog are from twcv bundles of the lumbar plexus. 

 When the upper one of the bundles was stirnulated with a tetanizing current the 

 gastrocnemius contracted, but if immediately after the application of the current 

 to the upper bundle the lower bundle was stimulated with feeble currents the con- 

 traction gave way to a relaxation. When strong currents were used for the stimu- 

 lation of the lower bundle at the time the upper was being stimulated, the relaxation 

 did not take place, but the original rise was accentuated. These findings can be 

 explained only on the supposition that there are in the muscular nerves of the 

 vertebrates inhibitory as well as excitor fibers. This conclusion, as has been hinted 

 at above, is in accord with results from other parts of the nervous system. 



Against the views of Bethe, Professor F. B. Hofmann (Innsbruck), H, con- 

 sidered some evidence regarding the nerve endings in his paper, "Zur Frage der 

 peripheren Nervennetze." The histological studies of the nerves going to the 



