Isidora antipodea, Sowerby (1873), sp.

Physa antipodea, Sowerby, Reeve, Conch. Icon., vol. xix., Physa, sp. 37 (1873). Physa antipodea, Hutton, Man. N.Z. Moll., p. 30. Aplexa antipoda, Hutton, P.L.S. N.S.W., vol. vii., p. 67. Bulinus antipodeus, Hutton, Trans. N.Z. Inst., vol. xvii., p. 56. Bulinus antipodeus, Hedley and Suter, P.L.S. N.S.W. (2), vol. vii., p. 627. Bullinus antipodeus, Suter, Journ. de Conch., vol. xli., p. 233.

Diagnosis in Hutton's Manual. I reproduce here (fig. 5) the outlines of the species after Reeve. This seems, as far as our scanty knowledge goes, to be the only one of our species that has constantly smooth whorls. The dimensions taken from the figure are—Shell: length, 22 mm.; breadth, 12 mm. Aperture: length, 13 mm.; breadth, 6½ mm. Rationis—i. = 1: 1.8; ii. = 1: 2; iii. = 1: 1.7.

Fig. 5.

This species is represented in my collection by two specimens from Lake Wakatipu, and the dimensions are—Shell: length, 17 mm.; breadth, 10½ mm. Aperture: length, 11 mm.; breadth, 5½ mm. Shell: length, 18½ mm.; breadth, 11 mm. Aperture: length, 12 mm.; breadth,