THE NATURAL HISTORY SURVEY. yal 
Geological distribution: Pleistocene; Loess. 
Habitat: Found rather sparingly in the crevices of rot- 
ting logs, under sticks, stones, etc., in damp places. 
Remarks: Corticaria is distinguished by its obtuse apex 
and peculiarly armed aperture. The latter is very variable, 
being either simple or with one or two small conical teeth. 
The shell is peculiarly long and cylindrical, resembling some- 
what Cochlicopa lubrica in general form. It is widely distrib- 
uted. 
Section BIFIDARIA Pilsbry (Sensu stricto) 1900. 
(Eubifidaria Sterki, 1893.) 
“Shell cylindric to turriculate; lamellz typical.” (Sterki.) 
90. Bifidaria procera Gould, pl. xxx, fig. 11. 
Pupa procera GOULD, Bost. Journ. Nat. Hist., Vol. III, p. 401, pl. iii, 
* fig. 12, 1840. 
Pupa carniata GOULD, Olizm, an abnormal shell. 
Pupa gibbosa SAY, Kiister, and P. minuta Say Pfr. (non Say). 
Pupa rupicola SAY, Binney, Man. Amer. Land Sh., p. 828, fig. 354 (non 
Say). 
Pupa Us PFR., Strebel, Beitr. Mex., Theil IV, p. 91, pl. iv, fig. 12; 
pl. xv, fig. 10. 
Pupa hordeacea GABB, Binney, Man. Amer. Land Sh.,, p. 178, fig. 165. 
Bifidaria procera cristata P. & V., Proc. Phil. Acad., p. 595, pl. xxii, 
figs. 4,5, 1900. (Variety.) 
Shell: Cylindrical, long, shining; surface covered with 
well-marked, oblique lines of growth, the apex smooth; color 
brownish or chestnut-horn; whorls six, convex, the last three 
about equal in size and the first three rapidly diminishing to 
the nucleus, making an obtuse apex; sutures deeply impressed; 
aperture ovate or semicircular, higher than wide; there are 
generally five teeth placed as follows: one on the parietal 
wall, large and somewhat compressed, long and bifid at the 
end; one on the columella, near the upper third, short, coni- 
cal; a third on the upper third of the outer lip, thick, conical, 
short; a fourth on the base of the peristome, long, sharp; and 
a fifth placed behind the columella tooth, large and massive; 
peristome rather widely reflected, thickened, bluish- white; ter- 
minations approaching and joined by a callus; umbilicus small, 
open (Fig. 63). 
Length, 2.50; diameter, 1.00; aperture length, 0.50 mill. (12821.) 
Animal: Resembling that of corticaria. 
