LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON

168 lower chetaceous deposits ijf california and oregon
only 1 mm, Like Bochianilta oottcri it may represent the stratigraphic position of
Bochianilet neocomi'eruti (d'Orbigny), The species has also been found near the
base of the Paakenta group, 2 miles northwest of Paskenta. Its range is throughout
the lower two-thirds of the group in its type district.
All the examples thus far found have been associated with Auc«Ifa cras&a, Aucella
infiata, and Aucella craaaicallit* Its horizon is thought to be lower and middle
Valanginian,
PARASOPLITIBAE Spath 1024
Parahoplitoidet Spath
Parahoplitoidcs thoupi Anderson, n. sp.
(PLOUTT, AFIU« 2)
Shell large, diaeoidal, somewhat compressed, involute, with moderately broad
umbilicus; sides flattened, closely costate, ribs broad, flexuous, arising at the whorl
suture, non-tuberculate, although swollen on tbe umbilical border in young stages of
growth, smooth in older stages, branching into pairs near the middle of the aide, and
all continuing serosa the periphery without interruption; ventral sone scarcely
flattened; section of whorl semi-elliptical, narrowing toward the periphery; whorl
thickeat a little above the middle of the aide; suture line not well exposed in the
holotype, but showing a tendency to asymmetry in the ventral zone and on the aides;
aiphonal saddle unsymmetrical, the siphonal notch inclining to the right; in thia
respect the suture resembles that of AcanlhopliUs remondi (Gabb).
The holotype (Calif. Acad. Sci. type Coll.) was obtained from the Shoup zone
en Bee Creek, immediately above the Argonaut tone on the Shoup ranch, 4 miles
south of Ono, Shasta County. It has about 06 ribs and has the following dimensions:
greatest diameter, 202 mm.; width of umbilieua, 62 mm.; height of whorl, B5 mm.;
thickness of whorl, SO mm. In form and ribbing this species closely resembles -Parahoplitoidu
latitat (Neumayr and Uhlig), although differing from it in some eutural
elements. The holotype waa found with PhyUoccras onotaac-, Tropaewn pcrcoaialutn,
and a few other species, a little above the Argonaut zone, and somewhat higher
above the horizon of Auttraliceraa argua, aa found on Bee Creek. The holotype ia
septate throughout and, when complete, must have exceeded 12 inches in diameter.
FarsAcpIifoides aeniloidea Anderson, n. sp.
mite 31, fleam 1)
Shell large, dtscoidal, somewhat compressed, involute; umbilicus relatively
narrow, aides costate only inyoung atagea, smooth in older stages; ribs Dexuous when
visible, tuberculate in young stages only; umbilicus bordered by abrupt walls, which
are rounded above, the curve merging with the almost smooth sides; periphery
rounded in holotype. The holotype (Calif. Acad. Sci. type Coll,) has the following
measurements: greatest diameter, 241 mm. (9.5 inches); diameter of umbilicus, 57
mm.; height of whorl, 60 mm,; thickness of whorl, flOmm.; umbilical ratio, 0,236:1.
All examples of this genus so far found have occurred in the Argonaut zone, characterised
chiefly by Lytoceraa arsonaularum and Phylloceroa orwense.
This species cloflely resembles Parahoplitoidet laesiuxciiluA (von Koenen), in form
and ornamentation although it may be somewhat thicker in section. The horizon i s
the same as that of Parahoptiim'dcs shoupi.
Parahoplitftidfti ccrrosensis Anderson, n. ap.
(Pint* 33. Ggtra I)
The strongly costate shell of this spcciea is rather large, discoidal, compresacd,
with a moderately broad umbilicus; ubout 34 peripheral costae, somewhat flattened.