LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON

description of species 157
related to "Craspeditts" tenuis (von Kocnen), which this author regards aa of Hauterivian
age, Spath cites other species of this genus in tho lower Hauterivian zones
at Speeton, England. The holotype has the following dimensions (partly estimated):
greatest diameter, 185 nun.; width of umbilicus, 66 mm.; height of whorl,
55mm.; thickness of whorl, 60 mm.; umbilical ratio, 0.336:1.
The species is found at Locality 1353 (Calif. Acad. Sci.), associated with Lytoeeras
traski nov., Phylloceras occidentals nov., Aeroteuthis kemensit nov., /noceramus
colonicus nov., and many other molluscan species of Hauterivian age.
.Yeoerofpedifos recloria Anderson, n. sp.
(?i*C« 33, firurt 3)
Shell of moderate eiie, discoidal anguatumhilicate, moderately inflated, umbilical
walls steep, rounded above, merging with the slightly convex sides; sides with many
costae; umbilical ribs arising on the walls, inclined backward, curving strongly
on crossing the border, swelling slightly near the middle of the side, and branching
here into four, sometimes five, finer costae, all with forward inclination crossing the
side, and also tbe periphery, without interruption; suture line only imperfectly
exposed. The holotype of the species (Calif, Acad- Sci. type Coll.) was found at the
mouth of Rector Creek, near Ono, Shasta County, about 50 feet beneath the bed
containing the preceding species. It appears to belong to the group of N. semilaevis
(von Kocnen), although occurring in somewhat younger beds, which are regarded as
lower Hauterivian in age. Von Koenen refers his Bpecies with some doubt to tho
lower Valanginian of Osterwald.
The holotype of the present species consists of an inner coil, septate throughout,
having the following dimensions: greatest diameter, S3 mm.; width of umbilicus, 11
mm.; height of whorl, 25 mm.; greatest thickness, 25 mm.; umbilical ratio, 0.208:1.
Afeocratpeditea siffnaiis Anderson, n. sp.
(Pint* M, %uru 1)
Shell rather large, discoidal, slightly inflated, section of whorl flatly semi-elliptical,
aides slightly flattened; umbilicus of moderate width, walla abrupt, rounded
on the border; ventral border rounded; sides numerously coetate, the riba arising
on the umbilical walls as coarse ridges, inclining at firBt backward, but above the
umbilical border bending gently forward, then dividing into two or three rather
straight costae, which are rather fine and rounded, and which cross the periphery
without interruption; suture line partly shown in the figure. The holotype (Calif.
Acad, Sci. type Coll.) was found by Mr. M. A. Wilcox on the eastern portion of his
ranch, 5 miles north of Paskenta, Tehama County. According to bis statements it
was found abovo the zone containing -4 ueella erasiuollis, which also contains Dichotomies,
Berriasella, and Bochianitca paskentaenaia, nov., but its more exact position
is not yet known. The holotype has the following dimensions: greatest diameter,
143 mm.; diameter of umbilicus, 56 mm.; height of whorl, AS mm.; thickness of whorl,
3d mm.; umbilical ratio, 0.392:1.
The holotype was not found associated with any other recognized form, although
it was not far from the position occupied by the foregoing and the following species.
Both are thought to represent the lower beds of the Horsetown group in the district
between McCarthy Creek and Elder Creek, Tehama County; they aid, therefore, in
tbe correlation of these beds with those of the Ono zone in the Cottonwood district,
Shasta County. Species of this genus have been found near Garzas Creek, on the
east flank of the Diablo Range, on the west border of the San Joaquin Valley.