. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. NEMERTEANS 273 Form and colour in life. The body is somewhat fusiform and in movement resembles Oerstedia in its semi-rigidity. The tail is more pointed than the head. Eyespots are visible in the smaller specimens. The colour is yellowish brown with a narrow median ventral pale "sole". The larger worms are darker and show less of the mottling—light irregular patches and dark spots—that is apparent in the smaller. There is a light ring circling the body at the back of the head, usually
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. NEMERTEANS 273 Form and colour in life. The body is somewhat fusiform and in movement resembles Oerstedia in its semi-rigidity. The tail is more pointed than the head. Eyespots are visible in the smaller specimens. The colour is yellowish brown with a narrow median ventral pale "sole". The larger worms are darker and show less of the mottling—light irregular patches and dark spots—that is apparent in the smaller. There is a light ring circling the body at the back of the head, usually behind the second pair of eyespots but sometimes coincident with them. This pale annulation is characteristic of the species in life. Form and colour of spirit specimens. Lengths 10 and 16 mm., breadths 07 and 1-4 mm. The body is nearly cylindrical, with the head thicker and blunter than the tail. There is sometimes a complete annular groove at the back of the head. The eyespots are not visible. The colour is usually completely bleached, but occasionally sufficient brown re- mains to display the white neck band. When cleared in anilin oil the pigment shows as black specks. The eyes, which are also rendered visible, are two pairs of brown cups, the con- cavity of the anterior pair being antero-lateral, that of the posterior pair postero-lateral. The eversible part of the pro- boscis is less than half the length of the body. Anatomy. The epithelium is very thick. The relative thick- ness of the body layers can be seen in Fig. 49. The head glands fill the head completely and extend back on all sides of the brain. Posteriorly they end dorsally with the dorsal ganglia, but they continue beneath the stomach and anterior caecum until the two forward diverticula of the latter join it. The diverticula almost reach the brain. The proboscis is well developed and possesses ten nerves. The armature consists of a slim main stylet on a rounded base and two reservoirs each with four, five
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
