SECTION OF NAKliD-KYLl) MEDUSAE. 107 



adjacent tentacles between wliicli no cut was made 

 continued unini|)aired, while the sympathy between 

 them and the other tentacles w^as destroyed. 



The nervous connections between the tentacles 

 and the manubrium are of a more general character 

 than those described between the tentacles them- 

 selves; that is to say, severing the main radial 

 nerve-trunks produces no appreciable effect upon 

 the sympathy between the tentacles and the 

 manubrium. 



The nervous connections between the whole 

 excitable surface of the nectocalyx and the manu- 

 brium are likewise of this general character, so that, 

 whether or not the radial nerve-trunks are divided, 

 the manubrium will respond to irritation applied 

 anywhere over the internal surface of the nectocalyx. 

 The manubrium, however, shows itself more sensitive 

 to stimuli applied at some parts of this surface than 

 it is to stimuli applied at other parts, although in 

 different specimens there is no constancy as to the 

 position occupied by these excitable tracts. 



Distribution of Kerves in Tiarojjsis Indicans. 



We have seen that in Sarsia reflex action obtains 

 between the manubrium and the nectocalyx; we 

 shall now see that in Tiaropsis indicans something 

 resembling reflex action obtains between the 

 nectocalyx and the manubrium. The last-named 

 species is a new one, which I have described else- 

 where, and I have called it " indicans " from a 

 highly interesting and important peculiarity of 



