. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 248 E. E. BALL AND J. F. CASE. , i ' \ II FIGURE 3. Variability in pulse patterns of one Corymorpha in response to single electrical stimuli; (A.) large pulses interspersed among a series of much smaller pulses; (B.) a single triggered pulse traveling distally has apparently initiated a burst of activity originating from the other end of the stalk. The significance of the apparent differences in initial polarity of large and small pulses is unknown. Stimulating and recording electrodes were in the same positions for each rec
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 248 E. E. BALL AND J. F. CASE. , i ' \ II FIGURE 3. Variability in pulse patterns of one Corymorpha in response to single electrical stimuli; (A.) large pulses interspersed among a series of much smaller pulses; (B.) a single triggered pulse traveling distally has apparently initiated a burst of activity originating from the other end of the stalk. The significance of the apparent differences in initial polarity of large and small pulses is unknown. Stimulating and recording electrodes were in the same positions for each record. Stimulus artifacts in the records are marked with upward-pointing arrows. Vertical scale equals 50 //V; horizontal scale equals sec. determined from a minimum of five measurements on each of eight animals was cm/sec. Individual averages varied from cm/sec to cm/sec. From these data it appears the TPS is non-polarized, although the possibility of normal input polarization is not eliminated by these experiments since electrical stimuli would be expected to activate the conducting system directly. Experiments in which stimulating electrodes were placed at the base and neck, with three recording elec- trodes between, show very similar-appearing pulses traveling base to neck and neck to base, respectively. Possible facilitation in the TPS. Some records have been obtained which might be interpreted as showing facilitation (Fig. 4). However, since the recordings were made with suction electrodes it is difficult to evaluate these results because the relation of the electrode to the underlying tissue and the strength of the suction can change over time as the animal expands and contracts. The distal opening response. Torrey (1904) and Parker (1919) describe the distal opening response in Corymorpha palma, and both Wyman (1965) and Krasilovsky (1967, unpublished) apparently had little trouble eliciting it in Cory- morpha palma and C. pendida, respectively. In the
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
