180 PROCEEDINGS OF THE ACADEMY OF [March, 
(3) Station C: Upper talus-slope in the bay about 4 mile west of 
Bass Camp, a few hundred feet below the rim. The shells here are 
small, alt. 8, diam. 13, width of umbilicus 2mm. None found alive. 
In some examples the shoulder-band is extremely faint, but in most 
of them it is distinct. 
(4) Station A: ‘Spectacle Cove,’ an embayment at the foot of 
the cross-bed or Coconino sandstone, in a talus resting upon the Aubrey 
red sandstone, with Oreohelix yavapai profundorum. 
Specimens measure: 
Alt. 10, diam. 16.0, umbilicus 2.1 mm. 
6c 9, a3 14.8, ce 2A) a3 
All have a band at the shoulder. Very few living adults were 
taken, but, unlike the Oreohelices, the shells are entirely normal. 
(5) Seep Spring, 2 miles west of Bass Trail, at base of the cross-bed 
sandstone. Shells like the preceding lot from the same level. 
(6) Station B: Head of Starvation Tank Wash, around the point 
to the right from Bass Trail, at about 5,800 feet elevation (Pl. XII, 
figs, 29, 30). 
(7) Station D: Bass Trail, on the Red Wall, 5,000 feet. 
Alt. 10.1, diam. 16, umbilicus 2.1 mm. 
CO eae aan LO, i Ded Wer 
Beier (Lee Ae hae 
The shoulder-band is wanting in about half of the shells taken. 
(8) Station E: Foot of Red Wall, on Bass Trail, elevation about 
3,850 feet. Like the preceding, diam. 15 to 16.3 mm. _ A few “‘bones”’ 
were taken still lower, at about 3,000 feet, in a talus of the Red Wall 
limestone. 
Alt. 8.9, diam. 15.0, umbilicus 2.0 mm. 
Fig. 29. “ 90, “ 143, “ 20 “ ;whorls 44. 
SOs) || Aelia 4 Ufa? he 
ew, “als spat 
The corneous, brown shell is more or less streaked with white and 
invariably has a narrow band at the shoulder. 
(North Side of the Colorado River.) 
(9) Station F: Shinumo Creek, near camp, elevation about 2,500 
feet. 
Alt. 10.8, diam. 16.9, umbilicus 2.1 mm.; whorls 44. 
Ci 10,8 Hoo 16a e amen, 5 
tb) gee ET oll BAe = nee lt 
Similar shells occurred at Station 3, Shmumo Box, 2,750 feet, 
