322 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 



It is surrounded by the peripharyngeal connectives 

 which connect the cerebral ganglia, lying dorsally, with 

 the sub-oesophageal ganglion or anterior end of the 

 ventral nerve cord. The pharynx can never be everted, 

 and is provided with exceedingly muscular walls, the 

 musculature being chiefly dorsal in position. The lumen 

 is folded and ciliated, the cilia being considerably longer 

 than those of the buccal cavity (PL II, fig. 4, ph.). 



4. The Oesophagus. The pharynx opens into the 

 oesophagus, which also extends through two segments 

 (4 and 5), and communicates at its posterior end with 

 the intestine. The oesophagus is a narrow tube, its lumen 

 somewhat folded and ciliated. The wall is thin, 

 consisting of a ciliated epithelium internally and a few 

 muscle fibres externally, arranged in circular and longi- 

 tudinal directions, the circular muscles inside (jig. 4, oe.). 



Situated in those segments occupied by the 

 oesophagus, and, to a less extent, those occupied by the 

 pharynx, are organs of a glandular nature known as 

 septal glands. These organs occur in many Oligochaeta, 

 but are specially well developed in aquatic forms, 

 although they have been described by Vejdovsky as being 

 very well marked in Allolobophora foetida. These glands 

 are attached primarily to the septa, but may extend on 

 to the walls of the oesophagus, and to a large extent lie 

 freely in the body cavity. Each gland is a mass of pear- 

 shaped cells, the narrower part of each being prolonged 

 into a duct which opens into the oesophageal region of 

 the alimentary canal. The cells possess very distinct 

 nuclei, situated in the broader part of the cell (PL II, 

 fig. 4, s.gl.). 



5. The Intestine. The intestine commences in 

 segment 6, and extends throughout the entire remaining 

 length of the body to the anus, which, as already stated, 



