Long-term patterns of gill cleaning, ventilation and swimming inLimulus

Abstract

1. The gill appendages ofLimulus are utilized for several different activities, all of which commonly occur in long-term patterns. These patterns consist of bouts of one type of activity alternating with bouts of another, in the following combinations (listed in order of prevalence): ventilation and gill cleaning, swimming and ventilation, swimming and apnea, ventilation and apnea, swimming and gill cleaning. 2. The long-term patterns are fairly stable, although there may be some variability in the duration of bouts within a pattern. These alterations in the bout duration do not appear to influence the length of the succeeding bout. 3. The patterns are susceptible to changes in ambient oxygen concentration. 4. It is suggested that the underlying neural mechanism responsible for generating these long-term patterns consists of bout generators for each fixed action pattern which reciprocally inhibit each other.