ARTIFICIAL RHYTHM. 



207 



specimen both before and after the operation. The 

 (^ketches are of life size, and drawn to accurate 

 measurement (Figs. 29 and 30).* 



Fig. 29. 



30. 



With regard to this remarkable effect on the 

 manubrium of removing the margin of the necto- 

 calyx, it is now to be observed that in it we 

 appear to have very unexceptionable evidence of 

 such a relation subsisting between the ganglia 

 of the nectocalyx and the muscular fibres of 

 the manubrium as elsewhere gives rise to what 

 is known as muscular tonus. This inter])retation 



* I may here mention that the fact of the manubrium of Sarsia 

 undergoing this extreme elongation after the removal of the mar- 

 ginal ganglia, serves to render the artificial rhythm of the organ 

 under the influence of injury, as previously described, all the more 

 conspicuous. 



