Figure 4. A–F in Character-matrix based descriptions of two new nemertean (Nemertea) species

Figure 4. A–F, Raygibsonia bergi gen. et sp. nov. A, section through anterior-most part of body showing cephalic glands, cerebral organs, oesophagus, and the poorly developed precerebral septum. B, section through cephalic region showing cephalic blood supply, stomach, and cerebral ganglia. Note the vascular plug (arrowhead). C, section through pyloric region showing the connection between pylorus and intestine. Note the myofibrillae in the lateral nerve cord (arrowhead) and the nerves of the proboscis (arrow). D, section through proboscis armature region of body showing the stylet apparatus. Note the accessory stylet (arrow) and the peripheral neural sheath (arrowhead) that connect the proboscis nerves. E, section through gonad region of body showing immature gonads (probably sac-like). Note the accessory lateral nerve (arrowhead). F, section through stomach region of body, showing distribution of gland cells. Abbreviations: AP, accessory stylet pouch; AN, accessory lateral nerve; CB, cerebral ganglion; CC, cerebral canal; CF, cephalic furrow; CG, cephalic glands; CL, dorsal lobules of cephalic glands; CM, circular muscle layer; CO, cerebral organ; D, dermis; DC, dorsal commissure; DG, dorsal ganglion; E, epidermis; ECF, cephalic gland encircling the foregut; G, gonad; I, intestine; IC, intestinal caecum; LD, lateral diverticula; LM, longitudinal muscle layer; LN, lateral nerve cord; LV, lateral blood vessel; MDV, mid-dorsal vessel; OE, oesophagus; P, proboscis; PE, proboscis epithelium; PN, proboscis nerve; PS, precerebral septum; PY, pylorus; R, rhynchocoel; RM, retractor muscle; S, stomach; SB, stylet basis; VG, ventral ganglion.