OF NORTH AMERICA. 205 



GIBBONS, Journ. Conch., II, p. 129, 1879. CR. and FISCH., Moll. Mex., II, pp. 

 47, 50, pi. 27, figs. 12, 12a, 1880. CLESSIN, Mai. Blatt, N. S., Ill, p. 83, 1881 

 CROSSE, Journ. de Conch., XXXVIII, p. 260,1890. PILSBRY, Proc. Phil. Acad., 

 1891, p. 320. CROSSE, Journ. de Conch., XXXIX, p. 157, 1891 ; XL, p. 35, 1892. 

 SIMPSON, Proc. Nat. Mus., XVII, pp. 438, 444, 1894. RHOADS, Nautilus, XIII, 

 p. 47, 1899. MARTENS, Biol. Cent. Amer. M,oll., p. 378, 1898. DALL and SIMP- 

 SON, Bull. U. S. Fish Com., XX, pt. 1, 369, 1900. FISCH. and CROSSE, Mis. Seient. 

 Mex. Moll., I, taf. 27, figs. 32, 32a ; II, p. 50, 1880. 



Lymnens cubensis SHUTTLEWORTH, Mitt. Natur. Ges., Bern, I, 1854, p. 98. 



LimncBus cubensis KUSTER, Conch. Cab., p. 32, taf. 6, figs. 6, 7, 8, 1862. 



Lymnea cubensis TRYON, Amer. Journ. Conch., II, p. 11, 1866. 



Lymncza cubensis HINKLEY, Nautilus, XXI, p. 78, 1907. WALKER, Nauti- 

 lus, XXII, pp. 7, 8, pi. II, fig. 3, 1908 ; Ottawa Nat., XXII, pp. 89, 90, 1908. 



Limnaa humilis SIMPSON, Proc. Dav. Acad. Sci.,' V, p. 69, 1896. JOHNSON, 

 Nautilus, III, p. 139, 1890. 



?Limncea umbilicata, C. B. ADAMS, Proc. Bost. Soc. Nat. Hist.,. II, p. 134, 

 1846; Contributions to Conchology, p. 45, 1849; Ann. N. Y. Lye. N. H., V, p. Ill, 

 1852; Contr. to Conch., No. 9, p. 187, 1852. 



Linmea umbilicata HENDERSON (on Adams), Nautilus, VIII, p. 33, 1894. 



?Limnea umbilicata CRANDALL, Nautilus, VI, p. 103, 1893. 



Lymncza lecontii LEA, Proc. Phil. Acad., 1864, p. 113; Journ. Phil. Acad., 

 VI, p. 162, pi. 24, fig. 79, 1866; Obs., XI, p. 118, pi. 24, fig. 79, 1867. SCUDDER, 

 Bull. Nat. Mus., 23, pp. 148, 201, 1885. 



Limnophysa lecontii TRYON, Amer. Journ. Conch., I, p. 255, 1865. 



Limncea lecontii TRYON, Con. Hald., Mon., p. 105 (79), pi. 18, fig. 4, 1872. 



SHELL : Small, ovate to roundly ovate ; periostracum light horn, 

 varying to pearl gray in some specimens ; surface with close-set, rather 

 rough and irregular lines of growth; spiral lines very faint; nuclear 

 whorls similar in outline to those of truncatula; under a power of 100 

 diameters the apical whorls appear finely striate; whorls 5^-6, well 

 rounded, rapidly increasing in size ; the whorls are usually inclined to 

 be shouldered; spire of medium length, broadly pyramidal or acute, 

 about as long as the aperture ; sutures well impressed ; aperture roundly 

 ovate, somewhat angled above ; periostome thin, acute ; inner lip folded 

 backward and forming a broad, flat, somewhat triangular expansion, 

 leaving a well marked umbilical chink; there is a very thin wash of 

 callus on the parietal wall; the axis is not twisted but forms a large, 

 wide, smooth, hour-glass-shaped column. 



Length. Breadth. Aperture length. Width. Locality. 



9.00 5.00 5.00 3.00 mill. Havana, Cuba 



8.00 5.50 4.50 3.00 " 



7.00 4.50 4.00 2.30 " 



11.25 7.25 6.25 3.25 " Cuba 



7.50 5.00 4.00 2.50 " Mexico 



10.50 6.00 5.50 3.00 " 



7.50 4.50 4.00 2.50 " lecontii 



