1. Serpulorbis zelandicus (Quoy and Gaimard) 1834

The first of the Milford species is clearly entitled to the original name proposed by Quoy and Gaimard for their neozelanic vermetid. The authors gave no description of the shell characters, merely remarking upon what has been pointed out above—the similarity of the shell to related species of Australian vermetids, and proceeding to describe the coloration of the animal. “Ce vermet a tellement de rapports avec V. elegans, que c'est avec doute que nous en faisons une éspèce particulière. On ne peut qu'indiquer ses couleurs. Těte jaunâtre en arrière, brun et ponctuée de rouge en avant. Le pied est seulement jaunâtre avec des taches rouges. Le manteau est largement bordé d'un orange vif. Le tube, contourné sur lui-même, ne nous a point offert de caractère appréciable sur le moment.” Reference to Quoy and Gaimard's atlas of zoological illustrations shows that the two coloured drawings of Vermetus zelandicus quite adequately identify the animal with one of the Milford species under consideration. The use of the term zelandicus was first confused by Suter, who quite unwarrantably annexed to Quoy and Gaimard's colour description an account of the shell of Hutton's Siphonium lamellosum.

Finlay (1930) thereupon rightly considered Hutton's shell to be identical with that described by Suter under Serpulorbis zelandicus, and was led to accord the latter name priority over lamellosum for Hutton's Siphonium. Serpulorbis zelandicus, however, applies validly to a separate shell, prior to and quite distinct from Hutton's species, and a fuller description is now provided.

The shell is moderately large and vermiform, sub-solitary or in small groups of two or three intertwined, seldom forming larger aggregates. The coiling is completely untwisted and the disposition of the whorls irregular or in two or three loosely coiled convolutions attached along the whole of one surface to the substratum, save for the apertural portion which is generally vertical so that the opening faces directly upwards. The aperture is circular in section, the attached sides of the tube flattened or irregularly moulded to the substratum, and the exposed surface regularly convex. The diameter regularly increases, reaching 8–10 mm, across the aperture of a large shell. The sculpture of the free surface is predominantly of longitudinal ridges of somewhat unequal size, consisting of several more prominent cords, separated by three to seven rather smaller riblets. The longitudinal sculpture is crossed at close intervals by small sharp rugae sometimes giving a finely scaled appearance to the living shell, and in the beach worn