358 THE CHICAGO ACADEMY OF SCIENCES. 
only for the reason that others may identify it, if collected in 
this region by any student. 
148. Campeloma rufum Haldeman, pl. xxxvi, figs. 4, 6. 
Paludina rufa HALDEMAN, Mon., p. 3 of wrapper, pt. 3, pl. iii, fig. 1, 
1844, 
Melantho gibba CURRIER, Amer. Journ. Conch., Vol. III, p. 112, pl. vi, 
fig. 3, 1867. 
Shell; Thick, but not heavy, elongately ovate or globose; 
color olive green to light horn, especially near the sutures, 
showing old peristome marks as in ponderosum; beneath the 
epidermis the shell is pinkish or reddish and the apex is pink- 
ish; surface shining, polished, smooth, linesof growth numer- 
ous, raised into conspicuous ridges here and there, crossed 
by more or less distinct spiral striae; sometimes malleated on 
body-whorl; apex small, rounded, pinkish, eroded in some 
specimens; spire obtusely conic, somewhat elevated; sutures 
well impressed; whorls five and one-half to six and one-half, 
convex on the sutures but rather flat-sided on the peripheral 
portion of the whorl; last whorl (at the aperture) from two- 
fifths to one-half the length of the entire shell; aperture ob- 
liquely ovate, narrowed above, pinkish within, bluish-white on 
the columella and near the peristome; peristome acute, sim- 
ple, sigmoid, terminations joined by a bluish-white callus, 
which is reflected over the parietal wall and covers the umbil- 
icus; base of shell rounded. Operculum as in decisum. 
Length, 29.00; width, 17.00; aper. length, 14.00; width, 9.00 mill. (8859.) 3) 
«9850; “- 14.50; “ 9 1800; “ 800 °° (ole 
“90.00; “ 18.00; « “1150; © 8.00 “01ND 
“9050; “ 18.00; “ 9 “ 1150; “ 7.95 “ (10115) g 
“97.00; «©. 19.00; “ “ 1450; “11.00 “  (12866.)9 
Animal; Not differing materially from deczsum. 
Radula: As in decisum. 
Distribution: Connecticut and Massachusetts west to 
Iowa, south to Tennessee and Alabama. 
Geological distribution: Pleistocene; Loess. 
Habitat: Found rather plentifully on muddy bottoms in 
rivers and lakes. 
Remarks: This distinct and beautiful species is generally 
confounded with deciswm, but may always be distinguished by 
the peculiar pinkish tinge of the substance of the shell beneath 
the epidermis, and the pinkish apex. In form the shell much 
resembles both decisum and obesum, as well as some forms of 
