Fig. 3. (A) Series of L-potentials induced in the same nematocyte by chemo-mechanically stimulating the cnidocil apparatus of a distant nematocyte (saturating amplitude). Time intervals between records as indicated. The stimuli 1–4 and 6 (left to right) stimulated the same cell (cell I) but stimulus 5 deflected the cnidocil apparatus of another nematocyte (stimulated cell II) and induced the discharge of its cyst. Thin arrows indicate T-potentials. The initial phases of the responses and stimuli in Aa are shown on an enlarged time scale in Ab. Note the trend in the amplitudes of the L-potentials and the correlated changes in their latencies. (B) Amplitudes of L-potentials plotted against the latencies of the same responses; both axes with logarithmic scales. Values of L-potentials that occurred associated with discharge of the cyst of the stimulated cell are marked by open symbols (N=136), those that occurred without cyst-discharge (N=164) are marked by filled symbols. Open and filled triangles represent potentials induced by purely mechanical stimuli; open and filled squares represent those induced by combined chemo-mechanical stimuli. Values are from 222 stimulated cells. (C) Peak voltages of L-potentials of three recorded cells (series as in A), plotted against the latency of the same responses. Each recorded cell is represented by one symbol (square, triangle or diamond), each pair of a stimulated and a recorded cell by a roman number. Data points of series I–II are from records shown in A. Filled symbols represent responses accompanied by the discharge of the cyst of the stimulated cell; open symbols represent responses not accompanied by discharge. Resting voltages of the recorded cells as indicated. Values of r are correlation coefficients; lines indicate linear regression. Differences between absolute peak voltages of discharge associated L-potentials are smaller than the amplitudes. (D) L-potentials induced in the same nematocyte (Stauridiosarsia) by chemo-mechanical stimulation of other nematocytes that diverged from the recorded cell by the angles , given above the records. Each of these responses was associated with cyst discharge of the stimulated cell. The rising phase of each response and stimulus shown in Da is shown at higher time resolution in Db.