offending body, to perhaps the _quadrant_ of the bell in which the stimulation is being applied. If the stimulation be now supplied at _e_, the localization on the part of the manubrium will be still more accurate; and if applied at _f_ (that is, _almost_ beneath one end of the cut A B), the manubrium may succeed in localizing quite correctly. These facts may also be well brought out by another mode of section, viz. by cutting round a greater or less extent of the marginal tissue, leaving one end of the resulting slip free, and the other end attached _in situ_. If this form of section be practised on Tiaropsis indicans, as represented at _g_ _k_ in the figure, it may also be observed that irritation of a distant point in the marginal strip, such as _g_ or _h_, causes the manubrium to move in various directions, without any special reference to that part of the bell which the irritated point of the marginal strip would occupy if _in situ_. But if the stimulation be applied only one or two millims. from the point of attachment of the marginal strip, as at _i_, the manubrium will confine its localizing motions to perhaps the proper quadrant of the bell; and if the stimulus be applied still nearer to the attachment of the severed strip, as at _j_, the localizing motions of the manubrium may become quite accurate. Again, with regard to _radial_ distance, if the cut A B in the figure were situated higher up in the bell, as at A´ B´, and the arc, _c_, _d_, _e_, _f_, of the margin irritated as before, the manubrium would be able to localize better than if, as before, the radial distance between A B and _c_, _d_, _e_, _f_ were less. The greater this radial distance, the better would be the localizing power of the manubrium; so that, for instance, if the cut A´ B´ were situated nearly at the base of the manubrium, the latter organ might be able to localize correctly a stimulus applied, not only as before at _f_, but also at _e_ or _d_. In such comparative experiments, however, it is to be understood that the higher up in the bell a cut is placed, the shorter it must be; for a fair comparison requires that the two ends of the cut shall always touch the same two radii of the nectocalyx. Still, if the cut is only a very short one (say one or two millims. long), this consideration need not practically be taken into account; for such a cut, if situated just above the margin, as represented at _a_, will have the effect of destroying the localizing power of the manubrium as regards the corresponding arc of the margin; but if situated high up in the bell, even though its length be still the same, it will not have this effect.