The Question of Tonus in Skeletal Muscle. 177 



That a similar quantitative relation can be demonstrated in 

 anaphylactic animals tested directly with the foreign protein is 

 shown in the following table: Here an excess of the foreign protein 

 above a certain definite dose per body weight results in a decrease 

 in the toxic effects (percentage of deaths). 



The guinea-pigs here reported were sensitized by subcutaneous 

 injections with 0.01 c.c. pooled human serum. They were tested 

 14 days later by intravenous (jugular) injections with pooled 

 human serum. Test dose recorded as c.c. per 200 grams of 

 body weight. 



Test Dose. 



Animals 

 Tested. 



Died. 



3 to 8 Min. 



1 to 3 Hrs. 



Under 0.20 c.c 

 0.20-0.31 c.c. 

 0.34-0.37 c.c. 

 0.40-0.45 c.c. . 



8 

 23 

 S 

 7 



o 

 12 

 0 

 o 



108 (1040) 



The question of tonus in skeletal muscle. 

 By Theo. C. Burnett. 



[From the Rudolph SpreckeVs Physiological Laboratory of the 

 University of California.] 



The idea that the tonus of skeletal muscle is dependent upon 

 the sympathetic system, as asserted by De Boer, 1 is an attractive 

 one, as it brings the tonus of striped muscle into the same category 

 with vaso-constriction and vaso-dilation ; but De Boer having 

 been criticized by Beritoff, 2 it was determined to work out the 

 problem independently, in order to arrive at a definite conclusion 

 if possible. The work has been done on frogs at intervals during 

 the winter, but it was not intended to publish until the results of 

 experiments on mammals had also been ascertained, if at all. 

 The appearance of an article by Yas Kuno, 3 however, in the current 

 number of the Journal of Physiology, has determined me to publish 

 my results on frogs, as they seem to be confirmatory of his findings. 



1 DeBoer, S., Folia Neuro-biologica, Vol. 7, 1913, p. 378. 



2 Beritoff, J. S., Folia Neuro-biologica, Vol. 8, 1914, p. 421. 

 s Kuno, Yas, Jour. Physiol., Vol. 49, 1915, p. 139. 



