The Atoll of Funafuti, Ellice group : its zoology, botany, ethnology and general structure based on collections made by Charles Hedley of the Australian Museum, Sydney, N.S.W.
Euchelus Instrictus, Gould
Euchelus Instrictus, Gould.
Pilsbry, op. cit., p. 441, pl. lxvii., figs. 62, 63.
A single dead specimen from the beach of the Funafuti lagoon.page 406
Schmeltz quotes this from Fiji and Samoa. There are specimens in this Museum from New Caledonia.
Shell with spire scarcely elevated, rather widely umbilicated. Colour white. Whorls three, flattened below the suture, rounded at the periphery and concave at the base. Sculpture:—the last whorl is ornamented by about twenty, broad, squarely projecting, transverse ribs, which arise at a distance from the suture, enlarge to the periphery and continue to the basal angle, these ribs vanish on the penultimate whorl; close, regular and fine, raised, spiral lines cover the whole shell, crossing the ribs and interstices alike; these are in their turn overridden by transverse microscopic threads. Base excavate in the centre. Umbilicus one-fifth of the shell's diameter, exhibiting the previous whorls. Aperture round, lip thickened, above spreading on the previous whorl and at the base projecting a callus tongue into the umbilicus. Major diameter 1·8; minor 1·4; height "75.
Three specimens from sand on the lagoon shore, all of which are unfortunately broken at the aperture.
This closely resembles Cyclostrema archeri, Tryon* from Singapore, which is rather larger and more closely ribbed, but the basal callus on the lip of the present form has decided me in considering it generically and therefore specifically distinct from that.
* Man. Conch, x., 1888, p. 89, pl. xxxiii., figs. 84, 85.