The following communication contributes to our knowledge of two distinct aspects of annelid physiology.
The experiments on the isolated oesophagus were made as follows. The oesophagus was cut through immediately posterior to the pouches of the first diaphragm and again immediately anterior to the oesophageal glands, and removed. In this way almost the whole of the oesophagus was isolated, excepting only one short part between the oesophageal glands and the stomach, and another lying in front of the first diaphragm. In most of the experiments the oesophagus was then divided into two by a transverse cut about half-way along its length, and the oral and aboral halves were separately studied. They gave somewhat different results.
The pieces of oesophagus thus dissected were tied at both ends and suspended in sea water. Light isotonic levers were used in all the experiments to be described in this paper.
The oesophagus preparations were...
