Meeting Abstract
The primary mechanisms for steering during slow and fast swimming in the Pteropod mollusc Clione limacina include flattening and bending of the tail. The tail musculature includes well-develop longitudinal muscle bands, circular muscle, and dorso-ventral muscles. Since the muscles are associated with a central hemocoelic cavity, the longitudinal bands produce bending, while the dorso-ventral muscles flatten the tail. The circular muscle serves to increase tail length. All three contribute to the increase in fluid pressure that occurs during the change from slow swimming to fast swimming. Serotonin innervation of the tail musculature, primarily by two symmetrical pairs of neurons in the pedal ganglion, suggest peripheral modulation of the tail musculature during fast swimming.
