430 ELECTRO-PHYSIOLOGY CHAP. 



some way or other to the remainder. Here again, after the 

 shortest excitation, the contraction is prolonged, and of a tetanus 

 character analogous to that of compressed muscle. 



Total excitation of the entire sartorius also occurs at the 

 beginning of desiccation, if the muscle is partially split longi- 

 tudinally (Kiihne's " bifurcate experiment "), one half only being 

 directly or mechanically excited. Both halves are then seen to 

 contract simultaneously, and since the experiment also succeeds 

 when the connecting bridge of muscle is barely ^- cm. long, the 

 purely mechanical action of the directly excited bundle of fibres 

 upon the adjacent half could hardly be an adequate stimulus 

 within the short tract in which it is effective. Thus there is 

 almost complete coincidence between the response of a dried and 

 isolated, and that of a fresh, partially compressed sartorius. 



This also appears from experiments, in which the excitation 

 is transferred from one sartorius to a second in close juxtaposi- 

 tion. If two suitable muscles are laid together by the broad, unin- 

 jured, pelvic ends, so that the dry outer surfaces are coextensive 

 for about 1 cm., the two muscles react as a whole as an excitable 

 mass, cohering in every part, and conducting in all directions. 

 Not merely is each excitation of the one muscle, discharged by 

 any localised stimulus, propagated from fibre to fibre in the 

 same muscle, but the primarily excited muscle twitching as a 

 whole, throws the other also into secondary excitation. 



It was shown that desiccated muscles behave exactly like 

 compressed muscles, i.e. they respond to a short, single stimulus, 

 not as under normal conditions by a rapid twitch, but by falling 

 with great regularity into prolonged contracture, or a state of 

 persistent disquietude. In the latter case the secondary muscle 

 may be seen to follow each movement of the primary witli the 

 utmost exactness in every detail, as if the excitation were 

 directly transmitted from one preparation to the other. The 

 nature of secondary excitation from drying muscle to superposed 

 nerve is also remarkable, since it tells in favour of the dictum 

 that a rhythmical, discontinuous change of state corresponds with 

 the seemingly continuous contracture, after a single short excita- 

 tion. If the nerve of a sensitive preparation is laid longitudinally 

 upon an isolated sartorius undergoing desiccation, the leg falls at 

 each contracture into gentle secondary tetanus, without reference 

 to the nature of the stimulus, whether discontinuous excitation, or a 



