217 



only two East-Indian species in the collection appear to belong to the subgenus Lamelliconcha 

 Dali •'), the type of which is Hysteroconcha {^Lamelliconcha) concinna (Sowerby). 



I. Hysteroconcha {} Lamelliconcha) philippinarum (Hanley). (Plate VI, figs. 7 — 10). 



1844. Cytherea Philippinarum Hanley, Proc. Zool. Soc. London, p. iio. 



185 1. Cytherea Mendanae Philippi, Zeitschr. Malakozool., VIII, p. 72. 



185 1. Cytherea Philippinarum Sowerby, Thés. Conch., II, p. 627, pi. CXXXVI, fig. 176. 



1853. Meretrix Philippinaritm Deshayes, Cat. Conch. Brit. Mus., I, Veneridae, etc., p. 3g. 



1856. Cytherea Pliilippinarmn Hanley, Rec. Biv. Shells, p. 356, pi. XV, fig. 36. 



[857. Meretrix Philippinarum Adams, H. & A., Gen. Rec. Moll., II, p. 424. 



1860. Cytherea Philippinarum Reeve, Elem. Conch., II, p. 108. 



1863. Venus [Cytherea-Dione) Philippinarum Romer, Malakozool. Blâtt., X, p. ^6. 



1864. Cytherea Philippinarum Reeve, Conch. Icon., XIV, Cytherea, pi. X, figs. à,"] a,b. 



1868. Venus [Cytherea-Dione] Philippinarum Romer, Mon. Venus, I, p. 139, pi. XXXVII, 



figs. 2, a — e. 



1869. Meretrix Philippinarum Dunker, Cat. Mus. Godeffroy, IV, p. iio. 



1884. Cytheraea (sic) Philippinarum Grasset, Ind. Test. Viv., p. 266. 



1885. Cytherea [Dione] philippinarum Smith, "Challenger" Lamellibranchia, p. 141. 

 1890. Dione [Dione] Philippmarum Paetel, Cat. Conch. Samm., III, p. 73. 



1896. Dione Philippinarum Casto de Elera, Cat. Sist. Filip., p. 739. 



1898. Dione Philippinarum Melvill & Sykes, Proc. Malacol. Soc. London, III, p. 47. 



190 1. Dione Philippinarum Sturany, Denkschr. Kais. Akad. Wiss. Wien, Math. Nat. LXIX, p. 280. 



1903. Dione Philippinarum Hidalgo, Obras Malacol., II, p. 197. 



1905. Dione Philippinarum Hidalgo, Cat. Filip., p. 326. 



1906. Meretrix [Dione] Philippinarum Lamy, Bull. Mus. d'Hist. Nat. Paris, XII, p. 211. 

 191 1. Dione philippinarum Pelseneer, "Siboga" Lamellibranches (Anat.), pp. 52, 53. 



1928. Meretrix [Dione] philippinarum Faustino, Summary Philippine Mar. Freshw. Moll., p. 74. 



Romer's description of this species is very complète and his figures of the shell are 

 excellent. Young shells are somewhat trigonal, but the adults take on a more oval outline. The 

 sculpture consists of concentric, rounded ridges separated by slightly narrower, but deep and 

 regular furrows. 



The largest shell in the "Siboga" collection is rauch bigger than any of the shells so far 

 recorded; its measurements are: — length 23 mm., height 19.2 mm., diameter 13.7 mm. 



Distribution: — H. {} L.) philippinarum was described from the Philippines, and has 

 since been recorded from the Fiji Islands, the Andamans and the Red Sea. 



In the "Siboga" collection the species is represented by a good séries of shells of ail 

 âges from the Anchorage off Djankar, Java (St. 4), Bay of Pidjot, Lombok (St. 33), Bay of 

 Nangamessi, Sumba (St, 53), Bornéo bank (St. 80), the Anchorage off Lirung, Salibabu Island 

 (St. 133), Sanana Bay, east coast of Sula Besi (St. 193), Saleyer Anchorage (St. 213), Banda 

 Anchorage (St. 240), Kulewatti Bay, Dammer Island (St. 277) and Rumah-Kuda Bay, Roma 

 Island (St. 279). 



3. Hysteroconcha {) Lamelliconcha) dautzenbergi sp. nov. (Plate VI, figs. 11, 12). 



Hysteroconcha [} Lamelliconcha) dautzenbergi is closely allied to H. [IL.) philippinarum 

 (Hanley), but its shell is more trigonal and more tumid. The umbones, which are slightly more 



I) Dall, W. h. — Proc. U.S. Nat. Mus., XXVI, p. 354 (1902). 



STKOGA-KXPEDITTE LUI (T. 28 



