Conductivity in Nerve Trunks. 
37 
procedures without removal of the gland. There was no effect 
on the carbon dioxide output. 
In case I there was a distinct lowering of the carbon dioxide 
output, and a low level was established which persisted for sixteen 
days after the operation. At the end of this time the animal, 
which had previously been retaining nitrogen, was again in nitrogen 
equilibrium. On autopsy, an increase in fat and atrophy of the 
ovaries was observed. The weight of the animal had increased. 
In case 2 there was a lowered carbon dioxide output, although 
marked emaciation followed the operation. 
Case 3 lived but 48 hours after the operation. A respiration 
experiment was performed 24 hours after hypophysectomy. There 
was a markedly decreased carbon dioxide output, and an un- 
usually low nitrogen output for the same period. 
The apparatus used in these experiments was a modified Pet- 
tenkofer-Voit. The periods used for the determinations were six 
hours. 
22 (547) 
The influence of calcium and of sodium in M/10 solution upon 
the conductivity in nerve trunks. 
By DON R. JOSEPH and S. J. MELTZER. 
[From the Department of Physiology and Pharmacology of the 
Rockefeller Institute for Medical Research] 
In a previous communication before this Society 1 we reported 
that calcium chloride in an M/10 solution is capable of reducing or 
completely abolishing the direct and indirect irritability of frog 
muscles. The reduction or abolition is reversible ; sodium chloride 
restores rapidly the lost irritability. It was further found that 
the primary action of calcium does not affect both forms of irrita- 
bility in an equal manner; in a number of cases, especially under 
certain conditions of temperature and season, a comparatively 
small amount of calcium solution abolished completely the in- 
direct irritability (from the nerve) while the direct muscle irrita- 
bility still persisted in nearly its original intensity. From these 
experiments we concluded, among other things, that calcium af- 
1 Joseph and Meltzer, Proceed, of the Soc. for Exper. Biol, and Medicine, 
vol. vi, p. 104, 1909. 
