smith: on AUSTRALIAN MACTKID^. 145 



25. Mactra ornata, Gray. B.M. 



Mactra ornata, Gray, Mag. Nat. Hist., vol. i, p. 371 ; Reeve, fig. 58 ; 

 AVeiiikaiiff, p. 37, pi. xii, figs. 1-3. 



Hob. — Australia (Weinkauff), Chiua (Gray, Keeve), Ceylon (Brit. 

 Mus.), Queensland (Hedley). 



llecorded as Australian on the authority of Weinkauff and Hedley. 



26. Mactra (Mactrintjla) ovalina (Lamarck). B.M. 



Mactra ovalina, Lamarck, Anim. sans Vert., vol. v, p. 477, 1818; 



Keeve, fig. 66; Delesseit, lleciieil, pi. iii, figs, la, b. 

 M. depressa, Spengler, Skrivt. Naturliist.-Selsk., vol. v. Heft ii, 

 p. 118, 1802 (?) ; Reeve, pL xiv, fig. 67; WeinkauflP, p. 98, 

 pi. xxxiii, fig. 4; Smith, Challenger Lameliibranchiata, p. 57. 

 Mactrinula angulifera. Smith {no7i Deshayes), Report Alert Collec- 

 tions, 1884, p. 101. 



Hah. — Middle Port, Melbourne (Brit. Mus.), Australia (Reeve), 

 Port Curtis (Smith), Port Jackson {Challenger and Angas), Port 

 Phillip (Angas and Brit. Mus.). Hobson's Bay, Port Phillip, and 

 Western Port (Pritchard & Gatlifi"), Philippine Islands (Hidalgo). 



The Australian specimens are sometimes of a pale reddish tint, 

 especially towards the umbones. 



It is doubtful what the unfigured J/rtc^r^ depressa of Spengler, from 

 the coast of Guinea, may have been, but the shell figured and 

 described by Reeve under that name is certainly this Australian 

 species. The M. ovalina of Lamarck, from an unknown locality, 

 judging by Delessert's figures (Recueil, pi. iii, figs. 7«, b), is more 

 eijuilateral. However, this diflference may be due to an inaccuracy 

 on the part of the artist, for Dr. Gaston Mermod, of the Geneva 

 Museum, informs me that none of the three Lamarckian shells agrees 

 exactly with Delessert's figure, and the form of the pallial sinus, 

 alike in all three specimens, is not accurately depicted. 



He very kindly compared u specimen which 1 sent him with the 

 Lamarckian types, and he also sent me plaster casts of two of the 

 valves from that historic collection. He writes : "La coquille que 

 vous nous avez envoyee ressemble beaucoup aux exemplaires de 

 Lamarck. Cependant, il existe de petites differences." As these 

 slight differences may only be individual, I am inclined, at present, 

 to accept Keeve's identification of J/, ovalina, as figured in the 

 Conchologia Iconica. 



It is placed by Carpenti^r in the synonymy of M. frag His of 

 Chemnitz, another ill-defined and doubtful species, quoted by 

 Chemnitz from the Nicobar Islands, by Reeve from Honduras, and 

 by other authors from the West Indies, Brazil, etc. AVhat the 

 M. ovalina, Lamarck, quoted by Gray (King's Narrative of a Survey 

 of the Coast of Australia), may have been, is very doubtful, as I have 

 not been able to trace the specimens he had before him. 



Lamarck in 1818 described a 31. depressa from " les raers de 

 I'Inde", quoting Chemnitz (Conch. Cab., vol. vi, pi. xxiv, fig. 234) 

 as representing it. This tiguie, however, had already in 1790 been 



