SECTION OF xNAKED-EVED MEDUS.E. 119 



much fiirtlier from tlie manubrium, but in the course 

 of the radial tube /A;. 



And til is leads us to another point of interest. 

 In such a form of section, when any part of the 

 mutilated nectocalyx is irritated, the manubrium 

 shows a very marked tendency to toucli some point 

 in the tissue-mass a a d e (Fig. 23) by which it still 

 remains in connection with the bell, and throuirh 

 which, therefore, the stimulus must pass in order 

 to reach the manubrium. And it is observable that 

 this tendency is particularly well marked if the 

 section has been planned as represented in Fig. 23, 

 i.e. in such a way as to leave the tissue-tract a a d e 

 pervaded by a nutrient-tube d e, this tube being 

 thus left intact. When this is done, the manubrium 

 most usuall}^ points to the uninjured nutrient-tube 

 d e every time any part of the tissue-band a Z is 

 irritated. 



Let us now very briefly consider the inferences 

 to which these results would seem to point. The 

 fact that the localizing power of the manubrium 

 is completely destroyed as regards all parts of the 

 bell lying beyond an incision in the latter, con- 

 clusively proves, as already stated, that all parts 

 of the bell are pervaded by radial lines of differen- 

 tiated tissue, which have at least for one of their 

 functions the conveying of impressions to the manu- 

 brium. The fact in question also proves that the 

 particular effect which is produced on the manu- 

 brium by stimulating any one of these lines cannot 

 be so produced by stimulating any of the other 

 lines. But althoufrh these tracts of differentiated 



