140 GEOLOGICAL SURVEY OF THE TERRITORIES. 
ulated. That species differs from ours, however, in having its angle 
further from the proximal border of the volutions, and in wanting the 
numerous uniform revolving lines upon all the exposed surface of the 
volutions. 
Position and locality—-Carhoniferous strata at the Wild Band Pockets, 
Northern Arizona, 15 milcs southward from Pipe Spring, where Mr. Gil: 
bert found it associatec with Nuculana obesa, Allorisma gilberti, &e. 
Genus PLEUROTOMARIA Defrance. 
PLEUROTOMARIA TAGGERTI Meek. 
Plate 34, figs. 1 a and b. 
TENS taggerti Meek, 1874, An. Rep. U. 8. Geol. Sur. Terr. for 1873, p. 271 (foot 
note). 
This species was collected by Dr. A. C. Peale from Carboniferous 
strata near Horseshoe Mountain, South Park, Colorado, where he found 
it associated with Productus semireticulatus, P. nebrascensis, P. pratieni- 
anus, &e. The following is Mr. Meek’s description: 
‘Shell attaining a large size, turbinate, very thin, slightly longer than 
wide; spire depressed conical, a little shorter than the length of the ap- 
erture; volutions five to five and a half, flattened above to the slope of 
the spire, last one very prominent and angular around the middle, with 
the under side slightly convex and sloping inward nearly at right angles 
to the flattened slope of the upper side above the peripheral angle; 
suture nearly linear; umbilical region very slightly excavated and im- 
perforate; aperture rather large, subquadrate, with height and breadth 
apparently nearly equal; spiral band extremely narrow, occupying the 
peripheral angle of the body volution, and passing around only about 
its own breadth above the suture on those of the spire; surface nearly 
smooth, or showing only obscure lines of growth, with apparently merely 
the faintest possible traces of revolving striz. 
‘“‘ Height, about 2.60 inches; breadth, about 2.49 inches. 
‘In size and general appearance this fine species somewhat resembles 
P. missouriensis (Trochus missouriensis Swallow), but it may be at once 
distinguished by having its body volution, below the periphery, longer 
than the height of the spire above it, instead of flattened, as well as by 
wanting the distinct revolving lines of that species.” 
The above statement, that “the body volution below the periphery is 
longer than the height of the spire above it, is likely to be misunder- 
stood. Mr. Meek’s type specimen, the only one yet discovered, has the 
width of the body volution, as measured across the aperture in line with 
the axis of the shell, a little greater than the length of the spire beyond 
the upper or distal portion of the aperture. — 
PLEUROTOMARIA GRAYVILLENSIS Norwood & Pratten. 
Plate 34, fig. 5 a. 
Pleurotomaria gr ayvillensis Norwood & Pratten, 1855, Jour. Acad. Nat Sci., Philad., 
vol. 111, p. 75. 
Pleurotomaria g gr ayvillensis White, 1879, Bull. U. 8. Geol. Sur. Terr., vol. v, p. 219. 
Among the fossils brought by Mr. Gilbert from the Carboniferous 
. strata at Wild Band Pockets, 2 Northern Arizona, are a couple of imper- 
fect examples of a small Pleurotomaria, which corresponds, so tar as can 
