Dissected specimen. Roof of mantle cavity removed. Features seen through transparent dorsum of the head; colour intensity and contrast increased to define features.
1: outer lips.
2: anterior wall of buccal cavity containing jaw and inner lips.
3: odontophore.
A whitish salivary duct (4) runs laterally by each of the two dorsal folds (5) of the oesophagus. The ducts carry mucus from the salivary gland to the buccal cavity to lubricate the feeding process and bind the food particles brought in by the radula . The mucus does not have a digestive function. In the rear of the buccal cavity, the mucus-bound food particles pass into the entrance of the oesophagus (6) and the radula (7) passes into the radular sac directly below the oesophagus (8) (so out of sight in dorsal view). Lubricating mucus is provided to the oesophagus by the oesophageal gland; a series of tubules on either side of it (9).
10: ctenidium.
APPENDIX re range advance/retreat: flic.kr/p/2jW74ig