Geology of the St. Croix Dalles. — Bcrkcy. 285 
gatus), group a, var. erectiis, b, \ar. attemiatiis, c, \ar. trimtifiifatus, cf, 
var. mayginatiis. 
Hypseloconus cornutiformis, n. sp. 
Plate XIX, Fif,'s. 11 and 12. 
Form high and curved far beyond the posterior margin, forming 
one quarter volution; surface smooth; curve regular; aperture a 
ilattened oval acuminate anteriorly; hight above base 30 mm; length 
18 mm; width 12 mm; apical angle small; apical excentricity 7-10 
mm. beyond the broad margin. The apex of the specimen is defec- 
tive. 
Formation and locality: Upper Dresbach, Taylor's Falls. 
Hypseloconus capuloides, n.» sp. 
Plnte XIX, Figs. 19 and 20. 
Shell small, high, strongly curved equal to one-third volution; surface 
smooth; aperture entire and much flattened; highest part of shell im- 
mediately above posterior margin, extremity curved slightly down- 
ward. Hight 10 mm.; length 8 mm.; width 4^ mm.; apical angle 
-small; apical excentricity 2 mm. beyond margin. 
Formation and locality: Upper Dresbach, Taylor's Falls. 
Hypseloconus f ranconiensls, n. sp! 
Plate XIX, Figs. 17 and IS. Plate XXI, Fig. 10. 
Shell small, slender, uniformly coiled to one-half volution-; apex 
srnooth, curved downward and slightly inward beyond the posterior 
margin; aperture defective but apparently entire and oval; surface 
smooth; hight above base 10 mm.; length of base 8 mm.; apex 5 mm. 
beyond margin. 
Formation and locality: The Franconia sandstone, Franconia, Minn. 
This form might possibly be placed with the genus Eccylioiiipha/iis. 
But on account of the series with which it is associated it seems 
jjreferable to describe it with them as a representative of one of the 
extremes of variation in the genus. 
Hypseloconus cylindricus, n. sp. 
Plate XIX. Fi«s. 9 and 10. 
Form very high, conical, approximating a circular outline of sec- 
tion, but slightly compressed anteriorly; apex absent, but a slight in- 
clination is easily observed; sides almost straight; surface strongly 
growth marked even to extent of plications; apex subcentra! to sub- 
marginal. Reconstruction indicates these measurements; hight 25 
mm.; len<Tth 12 mm.; width 10 mm.; apical angle 20°. A smaller 
specimen measures 21, 8 and 6 mm. 
Formation and locality: Upper Dresbach, Taylor's Falls. 
This and the following form might possibly be classed with See- 
