2. Vesicoinya compressa sp. nov. (Plate V, figs. 5, 6). 



Vesicomya compressa is very closely allied to V. brevis Smith ^) from the Arabian Sea, 

 but is easily distinguished by its shell being much more compressed and not so inflated, its less 

 prominent umbones; the upper margin of the shell is much more curved, the posterior margin 

 more rounded and more délicate concentric sculpture. 



Measurements of the Holotype: — Length 35.9 mm., height 27.2 mm., diameter 12.8 mm. 



Habitat: — The unique Holotype of the species was brought up in a deep-sea trawl at 

 St. 18 (7°28'.2S., ii5°24'.6E., 10 18 mètres). 



3. Vesicomya winckworthi sp. nov. (Plate V, figs. 7, 8). 



The following" is a description of this new species : species of a large size ; shell ovate- 

 trigonal, subrostrate ; umbones prominent, prosogyrate, lunule impressed, not well defined; 

 escutcheon marked off by a broad ridge running from umbo to ventro-posterior angle of shell; 

 anterior end rounded above, subtruncate below ; posterior end narrowly rounded to a point ; 

 ventral margin very arcuate; surface sculptured with very thin concentric striae, lines of growth 

 indicated in some places; hinge normal-, palliai sinus well marked. Shell of a dirty white colour. 



Measurements of unique right valve: — Length 64 mm., height 45.5 mm., diameter 6.5 mm. 



Habitat: — A single right valve, the Holotype, was brought up in a deep-sea trawl at 

 "Siboga" St. 17 (7°28'.5S., ii5°28'E., 1060 mètres). 



Remarks : — I would not hâve described this new species from a single right valve, but 

 for the very peculiar shape and the very interesting locality whence the unique valve was obtained. 

 The species is associated with the name of my friend Mr R. Winckworth, who has done so 

 much to clear up the very confused state of the nomenclature of the Indian marine mollusca. 



Family Lucinidae. 

 Genus Lucina Lamarck. 



1799. Lucina Lamarck, Mém. Soc. Hist. Nat. Paris, p. 84. 



1807. Anodontina Link, Beschreib. Nat. Samm. Univ. Rostock, p. 156. 



1822. Lucina Children, Quart. Journ. Lit. Sci, Arts, XIV, p. 322. 



1850. Ltccina Reeve, Conch. Icon., VI, Lucina pi. I (explanation). 



1857. Lucina Adams, H. & A., Gen. Rec. Moll., II, p. 466. 



1887. L^ucina Fischer, P., Man. Conchyliol., p. 1142. 



1901. Lucina Dali, Proc. U.S. Nat. Mus., XXIII, p. 801. 



1903. Lucina Dali, Trans. Wagner Free Inst. Sci. Philadelphia, III, p. 135 1. 



1920. Lucina Lamy, Journ. Conchyliol., LXV, p. J'j. 



1925. Lucina Woodring, Miocène Mollusks from Bowden, Jamaica, Pelecypods etc., p. iii. 



1930. Lucina Stewart, Spécial Publication Acad. Nat. Sci. Philadelphia, III, p. 175. 



Since Bruguière's name published in 1797 as a legend on certain plates of "Encyclopéd. 

 Méthod." cannot be accepted, Lamarck (1799) must be taken as the author of the genus Lucina. 



i) Smith, E. A. — Ann. Mag. Nat. Hist., (7) XVIII, p. 261 (1906) and Illustr. Zool. "Investigator", Moll., pi. XX, figs. 7, 8 (1908). 



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