448 THE CHICAGO ACADEMY OF SCIENCES. 



the St. Lawrence River were all founded on specimens of catascopium 

 (pinguis) a fact ascertained by an examination of some of the original 

 specimens kindly sent to the writer by Dr. Whiteaves. A single speci- 

 men was detected among the shells collected by Mr. J. Macoun in the 

 St. Lawrence River below the mouth of the Montmorency River, 

 which was almost identical with the Lake Superior shells. As this 

 may have been a case of parallel development in catascopium (to which 

 species all of the other specimens belong) and in the absence of addi- 

 tional material it can scarcely be referred to apicina. 



Galba apicina solida Lea. Plate XLVIII, figure 2 ; plate 

 XLVII, figure 30. 



Limnaa solida LEA, Trans. Amer. Phil. Soc., VI, p. 94, pi. 23, fig. 91, 1839 ; 

 Obs., II, p. 94, pi. 23, fig. 91, 1839. WHEATLEY, Sh. U. S., p. 24, 1845. JAY, 

 Cat. Ed. 4, p. 270, 1852. SCUDDER, Bull. Nat. Mus., 23, pp. 20, 201, 1885. 



Limnea solida HALD., Mon. Limn., p. 36, pi. 11, figs. 11, 13, 1842. 



Limnaa solida DEKAY, Zool. N. Y., p. 75, 1843 BINNEY, Check List., p. 

 12, I860. CPR., Rep. Brit. Assoc., p. 674, 1864. BINNEY, L. & F. W. Sh. N. A., 

 II, p. 62, fig. 97, 1865. CPR., Smith. Misc. Coll., p. 160, 1872. SOWB., Conch. 

 Icon., XVIII, Lim., sp. 88, pi. 13, figs. 88 a, b, 1872. TRYON, Con. Hald. Mon., 

 p. Ill (85), 1872. CLESSIN, Mai. Blatt., n. s., Ill, p. 82, 1881. 



Limnophysa solida TRYON, Amer. Journ. Conch., I, p. 256, 1865. 



Limnceus solidus TROSCHEL, Ardiiv. fur Natur., II, p. 224, 1839. 



Limnaa bulimoides var. solida COOPER, Proc. Cal. Acad. Sci., IV, p. 96, 

 1870. 



SHELL : Acutely conic or elongate-ovate, very solid, periostracum 

 pale horn varying to whitish; surface shining, presenting a polished 

 appearance; lines of growth coarse and close-set, spiral striation 

 marked; nuclear whorls as in apicina; whorls 4 to 5, rather rapidly 

 increasing in size, body whorl somewhat flatly rounded ; spire elongated, 

 acutely conic ; sutures impressed ; aperture ovate, somewhat expanded, 

 particularly at the anterior end; the aperture is about half the length 

 of the shell; outer lip thickened with an internal, longitudinal varix; 

 inner lip broadly reflected, completely closing the umbilicus, and form- 

 ing a broad, flat expansion; parietal callus very thick and spreading 

 over the parietal wall ; axis slightly twisted, forming a distinct but not 

 sharp plait. 



Length. Width. Aperture length. Width. 



11.25 7.00 6.00 3.25 mill. Type. 



13.00 8.00 8.00 4.75 " Salmon River, Idaho. 



12.00 7.75 7.00 4.50 " " " " 



TYPE: One specimen, Smithsonian Institution, No. 118713. 

 TYPE LOCALITY: Willamette (Wahlamat) near its junction with 

 the Columbia River, Oregon. 



