288 



i835- Cardium retustan Deshayes in Laniarck, Anim. sans Vertèb., VII. p. 410. 

 1840. Cardium retnsnm Pfeiffer, Krit. Reg., p. 59. 



1840. Cardium snbretusuni Sovverby, Proc. Zool. Soc. London, p. i 10. 



1841. Cardium subretusum Reeve, Conch. Syst., I, p. 100, pi. LXXVII, figs. 24, 24. 

 1841. Cardium retusum Sowerby, Conch. Illustr., p. 7. 



1843. Cardium Retusum and C. Subretusum Hanley, Rec. Biv. Shells, pp. 142, 144, pi. XVII, fig. 29. 



1844. Cardinui retusum Potiez & Michaud, Gai. Douai, II, p. 178. 



1845. Cardium retusum Catlow & Reeve, Conch. Nomencl., p. 44. 



1845. Cardium subretusum and C. retusum Reeve, Conch. Icon., II, Cardium, pi. XIX, figs. lOO, 103. 



1850. Cardium Retusum Deshayes in Cuvier, Règne Anim., pi. XCIX, figs. 2, 2a — c. 



1853. Lnnulicardia retusa Gray, Ann. Mag. Nat. Hist., (2), XI, p. 41. 



1855. Cardium retusum Hanley, Ipsa Linn. Conch., p. 46. 



1855. Hemicardium retusum Berge, Conchylienbuch, p. 65. 



1857. Hemicardia [Lunulicardta] retusa Adams, H. & A., Gen. Rec. Moll., II, p. 459. 



1860. Cardium retusum and C. subretusum Reeve, Elem. Conch., II, p. 103. 



1862. Hemicardium [Lunulicardia) retusum Chenu, Man. Conchyliol., II, p. 112, figs. 524, 525. 



1869. Cardium subretusum von Martens, von der Deckens Reise, p. 66. 



1869. Cardium [Luuulicardia) retusum Rômer in Martini-Chernn., Conch. -Cab. (N. F.), X {2), 



Cardiacea p. 112, pi. VI, figs. i — 4. 



1870. Hemicardia [Lunulicardia) subretusa MacAndrevv, Ann. Mag. Nat. Hist., (4) VI, p. 447. 

 1872. Hemicardia [Lunulicardia] retusa Tryon, Amer. Journ. Conch., VII, p. 272. 



1874. Cardium retusum von Martens, Vorderasiat. Conch., p. 104. 



1878. Cardium [Lunulicardia) retusum Kobelt, Illustr. Conchylienbuch, p. 346, pi. CI, fig. 5. 



1879. Cardium retusuvi von Martens, Monatsber. Akad. Wiss. Berlin, p. 743. 



1880. Cardium [Hemicardium) retusum and C. [H.) subretusum, von Martens, MtJbius Beitràg. 



Meeresf. Mauritius, Seychell., p. 324. 



1884. Hemicardiuui retusum and H. subretîisum Grasset, Ind. Test. Viv., p. 277. 



1884. Hemicardiuiii [Lunulicardia) retusa Tryon, Struct. Syst. Conch., III, p. 195, pi. CXVI, fig. 92. 



1887. Cardium subretusum von Martens, Journ. Linn. Soc. London (Zool.), XXI, p. 210. 



1890. Hemicardium [Lunulicardia) retusum and var. subretusum, Paetel, Cat. Conch. Samm., 



III, p. 119. 



1890. Cardium retusum Vassel, Bull. Soc. Nat. Hist. d'Autun, III, p. 26. 



1895. Cardium retusum Pilsbry, Cat. Mar. Moll. Japan, p. 131. 



1898. Cardium [Lunulicardia] subretusum Melvill & Standen, Journ. Conch., IX, p. 82. 



1899. Hemicardium subretusmn Melvill & Standen, Journ. Linn. Soc. London (Zool.), XXVII, p. 192. 



1900. Lunulicardia retusa Dali, Proc. U. S. Nat. Mus., XXIII, p. 385. 



1901. Hemicardium retusum Sturany, Denkschr. Kais. Akad. Wiss. Wien, Math. -Nat., LXIX, p. 283. 

 1903. Hemicardium subretusum Hidalgo, Obras Malacol., II, p. 356. 



1905. Hemicardium subretîisum Hidalgo, Cat. Filip., p. 347. 



1906. Cardissa [Lunulicardia) subretusa Standen & Leicester, Ceylon Pear! Oyster Rept., V, p. 292. 

 1906. Cardium retusum Owston, Japan. Loochooan Shells, p. 39. 



1909. Hemicardium [Lunulicardia] subretusum, Melvill, Trans. Linn. Soc. London (Zool.), 

 XIII, p. 135. 



1909. Hemicardium [Lunulicardia) retusum Lynge, D. Kgl. Dansk. Vidensk. Selsk. Skr. Nat.- 



Math., (7) V, p. 260. 



19 10. Opisocardium subretusmn Hedley, Austral. Ass. Adv. Sci., XII, p. 348. 



191 1. Hemicardium retusum Pelseneer, "Siboga" Lamellibranches (Anat.), pp, 55, 56, 57, 



pi. XXL fig. 5. 



1928. Cardium [Hemicardium) subretusum Faustino, Summary Philippine Mar. Freshw. Moll., p. 64. 



1929. Cardium [Hemicardium) retusum Dautzenberg, Faun. Colon. Français., III, p. 590. 



The nodulation of the niiddle ribs, vvhich is the main distinguishing character between 

 L. rehtsa and L. subretusa, is not at ail constant ; the nodules may be well developed, reduced 

 or altogether absent. I, therefore, agrée with Lynge that the two species should be united. 



