LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
Create successful ePaper yourself
Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.
188 <strong>LOWER</strong> cretaceotffi deposits IN california <strong>AND</strong> oregon<br />
Puzjjto diadema Anderson, n. sp.<br />
(PI*tail, SHITM t, 10, 11, IS><br />
The four examples of this species, are small, discoidal compressed, with moderate!<br />
or small umbilicus and fine sinuous costae; umbilical walla sloping, rounded above<br />
and merging into the convex sides; surface of sides marked by three or four shallow,<br />
flexuous grooves, inclining forward, and crossing the ventral zone with a forward<br />
sinus; interspaces between grooves Occupied by 20 or more line costal lines;<br />
section of whorl narrowly elliptical. The holotype (Calif. Acad, Sci. type Coll.),<br />
almost wholly septate, baa the following dimensions; greatest diameter, 20 mm.,<br />
width of umbilicus, 5 mm.; height of whorl, 9 mm.; thickness of whorl, 0 mm.; umbilical<br />
ratio, 0.240:1.<br />
The diameter of the syntype is 16 mm.; thickness of whorl, 5 mm. All the examples<br />
ware found at Locality 1316-A (Calif. Acad. Sci.), a mile above the mouth of<br />
Hulen Creek, on the west branch, associated with Pusflstn bwnaventura and Douvilleictrat<br />
mammillalitm var., in the Buenaventura zone, in the lower part of the<br />
Hulen beds. Tbe form may be the precursor of Puioaia onom nov.<br />
Pujo^ia jimboi Anderson, n, sp.<br />
(pl»te fieun* 5. S- 7)<br />
DESMCCERNA Uhikawai SMITH (not JIMBQ), Calif. State MLN. Bur., Bull. 00, 1914,<br />
Folio, opp. front cover, fig. S; Jackass Flat, near Horsetown, Shasta County.<br />
Shell small, discoidal, compressed, numerously costate; umbilicus of moderate<br />
width, walls abrupt, rounded above; surface marked by eight slightly ainuoua grooves<br />
arising on the umbilical wall and crossing the ventral area with a forward sinus;<br />
younger whorls not showing grooves or costae crossing the periphery; interspaces<br />
hetween grooves occupied by aix or more small rounded costae, often dividing at the<br />
umbilical border, or near the middle of the aide, and stronger on the upper part of<br />
the whorl; sutures not known. The holotype (Calif. Acad. Sci; type Coll.), half<br />
septate, has the following dimensions: greatest diameter, 23 mm.; width of umbilicus,<br />
7 mm.; height of whorl, 10 mm.; thickness of whorl, 9 mm.; umbilical ratio,<br />
0.304:1. The largest example of this species yet seen measures 40 mm. in diameter.<br />
The parntype (Calif, Acad, ScL type Coll.) has tbe following dimensiona: greatest<br />
diameter, 19 mm.; thickneBB of whorl, 7 mm. The horizon is that of the uppermoat<br />
Horsetown group. Many examples were found in 1898 at Jackass Flat, a mile east<br />
gf Horsetown j meet of these were loat in the San Francisco fire of 1900. The holotype<br />
was among those recovered. The specie a differs from "Detmocsra*" ithikavmi<br />
Jimbo (1894) in section, being relatively thinner, the umbilicus being much smaller;<br />
it also has a greater number of transverse grooves; it aleo has only about 50 costae<br />
to the whorl. The horizon of the preeettt species is not younger than upper Albian,<br />
whereas Jimbo'a species is much later, perhaps Senonian.<br />
Puzoaia ertima Anderson, n, sp,<br />
(Pitta II, fluirei)<br />
This species occurs with the preceding in the uppermost beds of the Horsetown<br />
group in the Cottonwood district. The shell is small, discoidal, compressed, flattened<br />
on the sides, numerously costate; Umbilicus small, walls abrupt, rounded on<br />
the border; surface marked by five or more faint sinuous gToovea which cross the<br />
ventral area with a distinct forward sinua; interspaces occupied by eight or more<br />
fairly well marked, rounded costae; Suture line not shown. The holotype (Calif.<br />
Acad. Sci. type Coll,), mostly septate, has the following dimensiona: greatest diam-