SECTION OF NAKED-EYED MEDUSZ. 119 
much further from the manubrium, but in the course 
of the radial tube f k. 
And this 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 touch some point 
in the tissue-mass a a d e (Fig. 23) by which it still 
remains in connection with the bell, and through 
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, 
2.¢. in such a way as to leave the tissue-tract aa de 
pervaded by a nutrient-tube d e, this tube being 
thus left intact. When this is done, the manubrium 
most usually points to the uninjured nutrient-tube 
de every time any part of the tissue-band a J 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 although these tracts of differentiated 
