PLATE CV. 



FK;. 277. The recording tuning fork. 



FIG. 278. 



Diagram of 

 the muscles of 

 the thigh of a, 

 frog, anterior 

 surface, g, .sar- 

 torius ; itd.m., 

 adductor mag- 

 n us; r.i.teo- 

 tus iuternus 

 major; v. i., 



vastus interims, ad. I., adductor longus ; act. b., adductor 

 interims minor. 



I'll. 



brevis ; t, rectti 



FIG. 28o.-Mus.jle in a trough bearing two levers, in ord.r 

 o show the wave of muscular contraction. To the left 

 are wen the pointed electrodes and the c'amp fastening the muscle 

 thread connected with the lever. 



FIG. 281. A different disposition of the 

 levers, intended to show the same thing. 

 The levers seen below the platform on to 

 which the muscle is fastened, are connected 

 with slips which pass round the muscle 

 at different part* of ite length. 



FIG. 279. Dia- 

 gram of a muscle 

 curve as drawn on a 

 travelling surface, 

 c, the line described 

 by the point of the 

 lever connected 

 with the muscle; 

 a, the line described 

 by marking lever; 

 6, the line described 

 by the tuning- 

 fork. Tne vertical 

 line m marks the 

 moment of stimu- 

 lation, m' the be- 

 ginning, mz the 

 maximum, and in 3 

 the end of the 

 contraction of the 



