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“Terebella ehlersi Gravier.
Gravier (1906), p. 47, pl. V, figs. 45, 46. Gravier (1911), p. 130.
Ehlers (1913), p. 556.
In the previous expeditions only one or two individuals of this Antarctic species seem to have been obtained, but during the visit of the “Aurora” to Commonwealth Bay, as many as fifty specimens were procured. It is then evidently fairly abundant in that area, though not nearly so common as some other species of Terebellids. In some instances the label includes a note as to colour, which is “bright red.” The worm lives in depths of from 2-6 fathoms, though it seems to be commoner at about 25 fathoms, and less common at greater depths.
There is a slight discrepancy in the account given by the two authors as to the nature of the tube. I find that the membranous basis is covered with material which varies with the nature of the bottom ; in some it consists of rather fine sand grains, interspersed with fragments of brown algae, as described by Gravier. Other tubes consist of extremely fine grains of grey sand, looking like mud grains. Such tubes have thicker walls than those with coarser grains ; and it is such a tube that Ehlers describes. In both kinds I find echinid spines, and sponge spicules so embedded as to produce a smooth external surface.
One such tube measures 90 mm. long, with a diameter of 15 mm. at its upper end, and its wall is 3 mm. in thickness.
Most of the worms measure from 50-70 mm., with an anterior width of 7 mm.; some are larger than this, and one is 90 mm. long. Gravier, however, gives 100 mm. as the length of a specimen with 86 segments.
The number of notopodial bundles varies from 40, 43, 45 and 49 in those examined. Gravier gives 54 and Ehlers 48.
The number of ventral gland shields is 14, 15 and 16, in my specimens. Gravier found 14.
There is no need to add anything to Gravier's account.
Boat Harbour, —Among rhizoids of floating brown Alga (Dr. McLean). Boat Harbour, 2-4 fathoms. Station B, 25 fathoms.
Station C, 15-20 fathoms.
Station D, 45-50 fathoms. Station E, 55-60 fathoms.
Distribution .—South American Antarctic (Gravier), Kaiser Wilhelm II Land (Ehlers).”