LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON

230 LiOWEH CRETACEOUS DEPOSITS IN CALIFORNIA ANB OREGON
AeTQlsvlhis wtraJtrtaenaia Anderson, n. sp,
(PUto s, firm* l. Is)
The guard of the apecies is large and heavy, with thick, dense walls, and a relatively
narrow alveolar pit and phragmaeone, The guard ia suheircular in scction,
the lateral diameter being greater than the dorse-ventral; sides generally parallel
in the upper half, sloping to a blunt point below; phragmaeone and axis nearly central,
a little nearer the ventral side; alveolus apparently deep, the sides forming
an angle of 15.5 degrees; ventral groove deep and narrow, extending nearly the entire
length of the guard. The holotype (Calif. Acad, type Coll.) has the following dimensions:
length flucomplete), 147 mm.; dorso-ventral diameter, 30 mm-; lateral diameter,
35 mm.; depth and width of ventral groove, 6.5 mm.
This species is related to Acroteuthis shaHewris nov., from tho upper part of the
Paskenta group, of which it may be a precursor. When complete, this example must
have measured 160 mm. in length. The holotype was found by T. H. Crook on Elk
Creek, about 2i miles north of the Winslow bridge, western Glenn County, in the
lowest beds of the Paskenta group, Shasta aeries, a little above the basal conglomerate,
and $00 to 400 feet beneath the second conglomerate of the series.
Acrtfjeuifcia nuttarJftyepms Anderson, n. sp.
(P]»l« S3, flgiiTs M
The guard of thisapecic-aia rather shortand robust, tapering uniformly to ft point;
guard sub-quadrate in section, thia feature forming one of its chief characteristics;
ventral surface flattened at the forward end, sulcata near the apes, with a rather
broad groove; phragmaeone occupying nearly one-half the length of the guard, axi-i
central. The holotype (Calif. Acad. Sei. type Coll.) has the following dimensions;
length, 115 mm.; diameter, 20 mm,; ventral groove about 50 mm. in length, extending
to the ape*.
This example wm found hy C. M. Cross at Locality 28107 (Calif. Acad. Sci.), on
McCarthy Creek, Tehama County, in a near basal bed of the Paskenta group. In
form, though not in size, it greatly resembles Acroteulhis aubquadralaa Rcemer, as
illustrated by Pavlow and Lamplugh (1892a, pi. 3).
Belemnappis Baylt (Hibolilcs de Montfort)
BeUmnopaia (Hibolitea) cignrroidei Anderaon, n. ap.
SO, figure 7}
Hibohtes rigaTr&ide* ANDERSON, Geo!. Sou. Am., Bull., vol. 44, 1933, p. 1264, "Zone
S," McCarthy Creek section, Tehama County.
The guard of this species is email, fusiform, tapering gracefully toward both extremities
from near the middle, terminating below in a sharply acuminate point;
ventral groove, if it exists, is scarcely visible, or is marked only by a flattened zone;
section of guard nearly circular; phragmaeone not exposed, axis seemingly central.
The holotype (Calif, Acad, Sci. type Coll.), the only complete example found, has
the following dimensions; length (incomplete), SI mm.; diameter at middle, 10 mm,
This specimen waa found in the lower part of the Horsetown group ("Zone T"),
on McCarthy Creek, Tehama County, about 1200 feet west of tho Lowry-Pflakenta
road. It was associated with AcrotetifA-ia ortocnjts nov. and fnocrrantus eotoaicua
nov. The apecies greatly resembles //iboiilwjaeidum (Phi lit pa) from the Neoeomian
of England and may possibly belong to the same group, The only other example
thought to belong to this genus—Behmnopzia dietniroidet—was found in nearly the
same horizon on Fiddler Creek, 10 miles south of One, Shasta County.