Nemertina
Morphological and anatomical features

Ne 1 , mature male Nectonemertes mirabilis in dorsal view, drawn to emphasise morphological features which may be seen either in stained whole mount or transparent live bathypelagic nemertines. Redrawn from Coe (1926).

Anatomical features of bathypelagic nemertines; all redrawn from Coe, 1926:

Ne 2abc , A-C: diagrams to show variations in rhynchocoel length in representative genera;
Ne 2de , D-E: diagrams to show differences in the organisation of the rhynchocoel musculature, comprising interwoven circular, longitudinal and spiral fibres (D), and primarily with outer circular and inner longitudinal muscle layers but with a few spiral fibres running among the circular muscles (E);
Ne 2fg , Ne 2hi , F-I, transverse sections through part of the intestinal regions drawn schematically to show differences in the arrangement of the lateral intestinal diverticula relative to the position of the lateral nerves;
Ne 2jk J-K: the organisation of the blood system, with mid-dorsal blood vessel extending the full body length (J), and with a short, rudimentary mid-dorsal blood vessel (K);
Ne 2l , L, ventral view of the head of a mature specimen showing the slender muscular penes which extend through the body surface from the spermaries.