SECTION OF NAKED-EYED MEDUS&. TZ 
it supposes to escape from a severed phalanx of 
nerve-fibres, and then to reach the manubrium after 
being diffused through many or all of the other 
radial lines (such stimuli thus converging from 
many directions), are responded to when they reach 
the manubrium, not by any decided localizing action 
on the part of the latter, but, as the hypothesis 
would lead us to expect, by the tentative and 
apparently random motions which are actually 
observed. Moreover, we must not neglect to notice 
that these tentative or random movements resemble 
in every way the localizing movements, save only 
in their want of precision. Again, this hypothesis 
is rendered more probable by the occurrence of 
those gradations in the localizing power of the 
manubrium which we have seen to be so well 
marked under certain conditions. The occurrence 
of such gradations under the conditions I have 
named is what the theory would lead us to expect, 
because the closer beneath a section that a stimulus 
is applied, the greater must be the immediate lateral 
spread of the stimulus through the plexus before it 
reaches the manubrium. Similarly, the further the 
circumferential distance from the nearest end of such 
a section that the stimulus is applied, the greater will 
be its lateral spread before reaching the manubrium. 
Lastly, the present hypothesis would further lead 
us to anticipate the fact that when Tiaropsis in- 
dicans is prepared as represented in Fig. 23, the 
manubrium refers a stimulus applied anywhere in 
the mutilated nectocalyx to the band of tissue by 
which it is still left in connection with that organ; 
