A technique for chronically recording the EKG of the lymph hearts in the toad Bufo arenarum (Hensel)

A simple technique for recording the EKG of the posterior lymphatic hearts of the toad Bufo arenarum (Hensel) in free moving unanesthetized specimens is described. This technique permits long term chronic recordings in varied physiological and behavioral conditions whereas it overcomes some of the technical difficulties encountered in obtaining reliable recordings.