Pecten imparvicostatus, Bavay (1905).

Pecten australis, Hutton, Journ. de Conch., vol. xxvi, 1878, p. 54; Man. N.Z. Moll., 1880, p. 171 (not of Sowerby). Pecten asperrimus, Hutton, Proc. Linn. Soc. N.S.W., vol. ix., 1884, p. 531 (not of Lamarck); Suter, Trans. N.Z. Inst., vol. xxxiv, 1902, p. 223; Index Faunæ N.Z., 1904, p. 93 (not of Lamarck). Pecten imparvicostatus, A. Bavay, Journ. de Conch., vol. liii, 1905, p. 23, pl. ii, figs. 6, 7.

Hab. Novæ-Zelandiæ mare. Collected by Dr. Gall, of H.M.S. “Archeron” (Bávay): Cape Maria van Diemen; Hauraki Gulf; Nelson; Foveaux Strait; Chatham Islands.

Type in the British Museum.

This species is the Pecten asperrimus of New Zealand conchologists. According to Bavay it stands nearest to P. aktinos(=bednalli, Tate), and also shows some affinity with P. bifrons, Lamk.(=tasmanicus, Ad. and Ang.) and P. lividus, Lamk.(=tegula, Wood).

P. gemmulatus, Reeve, is in my opinion an intermediate form between P. zelandiœ, Gray, and P. imparvicostatus, Bavay. The upper valve shows more or less characters of P. asperrimus, Lamk., but the lower valve is very different, and it never attains the size of the latter.