smith: on AUSTRALIAN JIACTRID^. 143 



18. Mactra incaknata, Deshayes. B.M. 



Mactra incarnata, Deshayes MSS. ; Reeve, pi. xiii, fig. 61 ; Weinkaiiff, 

 p. 108, pi. xxxvi, fig. 5; Smith, Chullenger Ij^moWihvixwchiOitn, 

 p. 58. 



Trigonella incarnata, Conrad, Aiuer. Journ. Conch., vol. iii. Appendix, 

 p. 37. 

 Hub. — Swan River (Reeve), Philippine Islands (Smith). 



19. Mactra jacksonensis, Smith. B.M. 



Mactra jacksone)isu, Smith, Challenger Lamellibrancliiata, p. 62, 



pi. V, figs. 9-9^. 

 Trtffonella piisilla, Angas (nee Adams), Proc. Zool. Soc., 1867, p. 916. 



Hab. — Port Jackson {Challenger), Port Darwin (Brit. Mas.), Mast 

 Head Reef, Capricorn Group, Qiieoiishmd (Hedley), Hog Bay, 

 Kangaroo Island, and Streaky Bay, Great Australian Bight (Tate), 

 otf Rhyll, Western Port, and otf Portsea, Victoria (Pritchard and 

 GatlifF). 



20. Mactra luzonica, Deshayes. B.M. 



Mactra luzonica, Desliayes, Proc. Zool. Soc, 1854, p. 64 ; Reeve, 

 fig. 81 ; Weinkauff, p. 49, pi. xvii, figs. 1, \a, 2, 2a. 



Trigonella luzonica, Angas, Proc. Zool. Soc, 1867, p. 916. 



Mactra apicina, Deshayes MSS. ; Keeve, fig. Ill; Hedley, Rep. 

 Aust. Assoc. Adv. Sci. 1909, p. 351, 1910. 



Hab. — Luzon, Philippine Islands (Deshayes and Hidalgo), Middle 

 Harbour and Botany Bay, Sydney (Angas), Queensland (Hedley for 

 apicina). 



M. apicina is not a white variety of M. opposifa, Deshayes, as 

 suggested by Weinkauff, but merely tlie young of the wliite variety 

 of M. luzonica. 



21. Mactra maculata (Chemnitz), Gmelin. B.M. 



Mactra maculata, Chemnitz, Conch. Coll., vol. vi, pp. 208, 217, 

 pi. xxi, figs. 208, 209 ; Gmelin, vol. vi, p. 3260; Reeve, fig. 56; 

 Weinkauff, p. 10, pi. iii, figs. 4, 5 ; pi. xvi, figs. 5, 6. 



Hah. — Nicobar Islands (Chemnitz), Philippine Islands (Reeve, 

 Hidalgo, and Weinkauff), Port Essington, Torres Straits, and 

 Claremont Island, North Queensland (Brit. Mus.), Goram Island, 

 Molucca Group (Brit. Mus.), Mast Head Reef, off Queensland 

 (Hedley). 



The single specimen from Torres Straits is entirely white excepting 

 the characteristic brownish stain within the valves at the hinder end. 



22. Mactra matthewsi, Tate. B.M. 



Mactra matthewsi, Tate, Trans. Roy. Soc. S. Aust., vol. xi, p. 60, 

 pi. xi, fig. 4. 

 Hab — Rovston Head, Spencer's Gulf, South Australia (Tate and 

 Brit. Mus.).' 



