Reflex Nervous Discharge. 



281 



For examining this point, we have again used tibialis anticus as muscle, and 

 as our spinal reflex the reflex evoked by faradisation of the popliteal 

 nerve, and then in the same preparation we have registered similarly the 

 maximal tetanus obtainable by direct faradisation of the motor nerve 

 (peroneal) itself. We employed the same frequency-rate of faradisation 

 for both reflex and direct effect, and both observations were obtained with 

 exactly the same registering apparatus, sometimes within four minutes of 

 each other. The myograph resistance was, as in our other observations, a 

 torsion-wire and the record isometric. The upper part of the scale of 

 resistance of the myograph was, within the limits of pull developed by the 



Fig. 6. — Maximal reflex (R) and maximal motor-nerve (M) responses of tibialis anticus 

 (spinal cat) obtained from same preparation, rate of faradisation 75 per sec. in each 

 case, and the secondary coil being at 12"8 cm. = 2000 Berne units for both. Under 

 each the signal recording the interruptions in the primary. 



muscular contraction, almost as open for the higher limits as for its range 

 near zero. The animals (cat) were young and small, and the maximal 

 tensions in different animals observed varied between 650 and 940 grm. 



Our results have been as follows : The ratio between the power of the 

 maximal tetanus of the spinal reflex and that of the maximal tetanus 

 obtainable by faradisation of the motor nerve is often unity, 1/1. In not a 

 few preparations it is somewhat less, exj., reflex/direct = 9/10; in some 

 preparations it is very markedly less, e.g., 6'5/10. 



That the maximal power of tetanic contraction obtainable from a muscle 

 reflex is often equal to the maximal tetanic power obtainable, under the 



