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Buchanan 



there no wa\-e.s in the records, these being of the type whicli in my previous 

 paper [(4), p. 146] I called " type i," and presenting a long series of wavelets 

 only (lasting for some 0-3 second) the frequency of which again varied 

 directly with the temperature of the muscle. This series of experiments 

 shows, therefore, that the frequency of the wavelet rhythm is dependent 



(Jastrocnemius of strychnine frog, D 82. Apr. 7, 1902. (Stimulation by 

 break induction shock to skin of the back, throughout.) Temperature 

 of spinal cord constant (12" C). 



on the muscle, but does not, of course, show that it is independent altogether 

 of the cord. This however is, I think, sliown by the second series of 

 experiments. 



Experiments in which the temperature of the spinal cord was 

 varied, and that of the recording muscle kept constant. 



A few of these were made in 1902, and se\eral more have been made 

 within the last year. The temperature of the cord was altered hy running 

 water at different temperatures through a glass tube passing under or over 

 the back of the frog, and so shaped that it went no nearer to the recording 

 muscle. The muscles used to record in these experiments were : the 

 gastrocnemius, the sartorius, the biceps and the triceps femoris, and the 

 semitendinosus. I shall have to refer later (p. 237) to differences of wavelet 

 rhythm characterising these different muscles. Here I will only give the 

 details of one typical experiment and reproduce two typical records. In 

 the experiment to which fig. 2 refers the triceps was the recording muscle, 

 the distal leading-otf electrode was on the tendon end and connected with 

 the mercury of the electrometer, the proximal one was about one centi- 

 metre away from it, and so on that part of the muscle in which there is no 



