20I 



more oblique and more inequilateral. The shells of this species are also more convex than of 

 the other two species, and the sculpture is less pronounced. 



Measurements : — Length 14 mm., height 10 mm., diameter 6.8 mm. 



Habitat: — The Holotype and 3 stray valves of A. weberi were brought up in a trawl 

 at St. 306 (8° 27' S., i22°54'.5E., 247 mètres). 



Genus Theora H. & A. Adams. 



1856. Theora Adams, H, & A., Gen. Rec. Moll., II, p. 369. 

 1864. Theora Adams, A., Ann. Mag. Nat. Hist., (3) XIII, p. 206. 

 1885. Theora Smith, "Challenger" Lamellibranchia, p. 90. 

 1887. Theora Fischer, P., Man. ConchylioL, p. 11 52. 

 19(4. Theora Lamy, Journ. ConchylioL, LXI, p. 297. 



The genus Theora was placed next to Neaera Gray by the brothers Adams, but was 

 later removed to the Scrobiculate Tellinidae by A. Adams. For a discussion of the hinge 

 référence may be made to Smith's work cited above. 



The génotype is Theora lata (Hinds). 



I. Theora iridescens (Hinds). 



1843. Neaera iridescens Hinds, Proc. Zool. Soc. London, p. 78. 



1844. Neaera iridescens Hinds, Ann. Mag. Nat. Hist., (i) XIII, p. 309. 



1845. Neaera iridescens Catlow & Reeve, Conch. Nomencl., p. 11. 

 1852. Neaera iridescens Jay, Catalogue (éd. IV), p. 15. 



1856. Theora iridescens Adams, H. & A., Gen. Rec. Moll., II, p. 370. 



1860. Neaera iridescens Reeve, Elem. Conch., II, p. 155. 



1864. Theora iridescens Adams, A., Ann. Mag. Nat. Hist., (3) XIII, p. 209. 



1868. Theora iridescens Tryon, Amer. Journ. Conch., IV, p. 118. 



1882. Theora iridescens Dunker, Ind. Moll. Mar, Japon., p. 181. 



1885. Semele {Theora) iridescens Smith, "Challenger" Lamellibranchia, p. 89, pi. V, figs. Ç>a, b. 



1890. Theora iridescens Paetel, Cat. Conch. Samm., III, p. 28. 



1895. Theora iridescens Pilsbry, Cat. Mar. Moll. Japan, p. 123. 



1903. Theora iridescens Hidalgo, Obras Malacol., II, p. 70. 



1905. Theora iridescens Hidalgo, Cat. Filip., p. 305. 



1906. Theora iridescens Owston, Japan. Loochooan Shells, p. 37. 

 19 14. Theora iridescens Lamy, Journ. ConchylioL, LVI, p. 298. 



I hâve nothing to add to Smith's very detailed description of Theora iridescens. The 

 shells collected by the "Siboga" Expédition consist of dead, odd valves only, but thèse are in 

 every respect similar to the types of the species from the Tsland of Luzon in the British Muséum. 



Distribution : — T. iridescens was described from the Island of Luzon, and has since 

 been recorded from Japan. 



The "Siboga" Expédition brought up a few dead shells in a trawl at St. 47"^ (Bay of 

 Bima; 296 mètres). 



SIBOGA-EXPEDITIE LlIIf. 20 



