315 



Full grown shells of 5. australis are transversely elongate ; the right valve is greatly 

 inflated, particularly in the umbonal région, while the left valve is only slightly convex. The 

 sculpture consists of irregular concentric striae. 



Distribution : — 5. australis has so far been recorded from the Australian waters. 



In the "Siboga" collection there is a single shell of the species collected in the Bay of 

 Nangamessi, Sumba (St. 53). 



Family Gastrochaenidae. 

 Genus Rocellaria Blainville. 



18 17. Gastrocliaena Cuvier, (nec Spengler) Règne Anim., II, p. 490. 



1829. Rocellaria Blainville, Dict. Sci. Nat., LVII, p. 244. 



1856. Rocellaria Adams, H. & A., Gen. Rec. MolL, II, p. 335. 



1862. Rocellaria Tryon, Proc. Acad. Nat. Sci. Philadelphia, p. 471. 



1887. Gastrocliaena Fischer, P., Man. ConchylioL, p. 1125. 



1898. Gastrocliaena Dali, Trans. Wagner Free Inst. Sci. Philadelphia, III, p. 823. 



191 5. Rocellaria Iredale, Proc. Malacol. Soc. London, XI, p. 297. 



1925. Gastrocliaena Lamy, Journ. ConchylioL, LXVIII, p. 286. 



1925. Gastrocliaena Woodring, Miocène Mollusks from Bowden, Jamaica, Pelecypods, etc., p. 191. 



A great deal of confusion has been introduced into the nomenclature of the family 

 Gastrochaenidae by the indiscriminate use of the generic names Gastrochaena and Fishilana. 

 I agrée with Iredale's conclusions that the name Rocellaria Blainville with Rocellaria dubia 

 (Pennant) as type, must replace Gastrochaena Cuvier of modem writers, while Gastrochaena 

 Spengler — type Gastrochaena mumniia Spengler, should be used in place oi Fistzilana Bruguière, 

 as adopted by récent workers. 



In the "Siboga" collection there are représentatives of two subgenera Rocellaria s.s.^ 

 and Spengler ia Tryon ■^) — type, Rocellaria {Spengleria) mytiloides (Lam.). 



I. Rocellaria {Rocellaria) macrochistna (Deshayes). 



1855. Gastrochaena macrochisma Deshayes, Proc. Zool. Soc. London (vol. for 1854), p. 326. 



1860. Gastrochaena macrochisma Reeve, Elem. Conch., II, p. 175. 



1862. Rocellaria macrochisma Tryon, Proc. Acad. Nat. Sci. Philadelphia, p. 480. 



1878. Gastrochaena macrochisma Sowerby in Reeve, Conch. Icon., XX, Gastrochaena, pi. IV, 

 fig. 29. 



1887. Gastrochaena macrochisma Sowerby, Thés. Conch., V, p. 129, pi. CCCCLXX, fig. 29. 



1890. Gastrochaena macrochisma Paetel, Cat. Conch. Samm., III. p. 8. 



1894. Gastrochaena macrochisma Clessin in Martini-Chemn. Conch. -Cab. (N.F.), XI, (4), Gastro- 

 chaena, p. 7, pi. IV, figs. 3, 4. 



1903. Gastrochaena macrochisma Hidalgo, Estud. Prelim. Faun. Malacol. Filip., p. 11. 



1925. Gastrochaena macrochisma Lamy, Journ. ConchylioL, LXVIII, p. 301. 



1928. Gastrochaena macrochisma Faustino, Summary Philippine Mar. Freshw. MolL, p. 115. 



The "Siboga" shells, which I assign to R. {R.) macrochisma, agrée with the types of 

 the species in the British Muséum (Nat. Hist.), London. 



i) Tryon, G. W. — op. cit., p. 472 (1862). 



