. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. J 64 DISCOVERY REPORTS proboscis pore is just ventral to the tip of the snout. The colour is blue-green, yellow- green, pale buff or light brown on the back, while the underside is always pale buff. The colour is deepest in individual worms on the hump caused by the proboscis. Occasionally a reddish tinge marks the position of the ganglia and a narrow whitish stripe at the margin of the body anteriorly the lateral glands. Form and colour of preserved specimens. After anaesthetization in chloral
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. J 64 DISCOVERY REPORTS proboscis pore is just ventral to the tip of the snout. The colour is blue-green, yellow- green, pale buff or light brown on the back, while the underside is always pale buff. The colour is deepest in individual worms on the hump caused by the proboscis. Occasionally a reddish tinge marks the position of the ganglia and a narrow whitish stripe at the margin of the body anteriorly the lateral glands. Form and colour of preserved specimens. After anaesthetization in chloral hydrate very little contraction appears to take place on fixing. The green colour is retained in spirit specimens for many months. The body does not change in shape but contraction causes two grooves to appear, one near the tip of the head, the other a little farther back. When only slightly marked these grooves take the form of two pairs of short lateral vertical furrows. Two irregular groups of very small eyespots—up to sixty—can be seen when the head has been cleared in anilin oil. The eversible part of the proboscis is apple green in colour. The anatomy of this species has been described by Hubrecht (1887) and Burger (1904 a, 1907). Variations occur in the following details. The eyespots, though always very small, vary considerably in number, and the pigment granules which they con- tain are of a deep green-blue colour. The lateral glands (very strongly de- veloped cerebral subepithelial gland cells) stain deeply with haematoxylin; the head glands less deeply. The number of nerves in the proboscis may be from eleven to six- teen though the usual number is fourteen. The base of the main stylet may be brown or green and there is a belt of brown gland cells round the armature. The base of the main stylet is less than twice as long as the stylet itself. The brain and cerebral organs are shown in Fig. 39. As noted by Burger (1907 (1912), p. 173) the dorsal ganglia lie latera
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