THE NATURAL HISTORY SURVEY. 277 



noc. Limmea palustris expansa Hald., pi. xxxii, fig. 2. 



Limncea expansa HALDEMAN, Mon., p. 29, pi. ix, figs. 6-8, 1842. 

 Limnceus sufflatus W. W. CALKINS, MSS. 



This form seems distinct enough to constitute a variety. 

 It is characterized by the spire and aperture being of equal 

 length, the whorls inflated and the aperture expanded and 

 shouldered at the upper part. In this area it has been found 

 only in the Calumet River. The figure is from Calkins' type of 

 sufflatus. 

 Length, 26.00; width, 13.00; aperture length, 15.00; width, 8.00 mill. (8375.) 



111. Limnaea ferrissi, N. Sp., pi. xxxi, fig. 26. 



Shell: Rather thin, elongated, scalariform, rimate; color 

 light horn; surface dull to shining, lines of growth conspicuous, 

 crossed by impressed spiral lines; whorls six, regularly in- 

 creasing, convex, the last almost round; spire sharply conic, 

 two-thirds the length of the entire shell; sutures deeply im- 

 pressed; apex rounded, deep wine color; aperture roundly 

 oval, one-third the length of the shell, brownish within; peri- 

 stome thin, sharp, continuous; columella reflected, thickened 

 by a callus, and with a faint plait; umbilicus narrow, deep. 



Length, 11.00; width, 5.50; aperture length, 4.50; width, 3.00 mill. 



Animal, jaw, radula and genitalia not examined. 



Distribution: Rock Run, Joliet, 111. 



Habitat: Similar to Limncea palustris. 



Remarks: Ferrissi has a strong resemblance to Limncea hol- 

 bollii Beck and Moll., and if collected in Siberia or Greenland 

 would certainly be so identified. The specimens under con- 

 sideration were collected by Mr. J. H. Ferriss in Rock Run, 

 near Joliet, and seem to constitute a very distinct species, 

 characterized by rounded, scalariform whorls. It does not 

 seem to be common and has been found only in Rock Run. 



112. Limnaea reflexa Say, pi. xxxii, fig. 6; pi. xxxi, fig. 1. 

 Limncea reflexus SAY, Journ. Phil. Acad., Vol. II, p. 167, 1821. 

 LimncEiis elongatus SAY, 1. c., p. 167, 1821. 



Limnceus palustris var. distortus ROSSMASSLER, Icon., Vol. I, p. 97, 



pi. ii, fig. 52, 1835. 

 Limncea lanceata GOULD, Proc. Bost. Soc. N. H., Vol. Ill, p. 64, 1848. 



(Variety.) 

 Ltmncea zebra TRYON, Amer. Journ. Conch., Vol. I, p. 228, pi. xxiii, 



fig. 4, 1865. 



Shell: Very much elongated, narrow, thin, sometimes 

 scalar; color honey-yellow to black, sometimes obscurely Ion- 



