LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
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202 <strong>LOWER</strong> <strong>CRETACEOUS</strong> <strong>DEPOSITS</strong> IN <strong>CALIFORNIA</strong>. <strong>AND</strong> <strong>OREGON</strong><br />
more gradually to the ventral border. A single constriction appears at a diameter<br />
of 70 mm. on the last whorl of the lectotype, which is septate throughout, but this is<br />
not found on all examples. The largest example found has a total length of ID<br />
inches, more than half of which is formed by the somewhat straightened arm, or body<br />
chamber.<br />
This species has been found on the Cottonwood Creek (Locality 1353, Calif. Acad.<br />
Sci.), and in the same zona on Eagle Creek, near Ono, where it was associated with<br />
Acroteuihi* kernemie nov,, Neosratpediti* ovutia nov,, Shazticrioeerai ponienie, and<br />
Itwceramtis cdlonicua nov,, all of which are found in the lowest beds of the Horsetown<br />
group in the Cottonwood district. Hoplocrioctras remondi has also been found in<br />
the middle part of the Horse town group in this district, in beds believed to be below<br />
the middle of the Paskenta group, as at Locality 1665 (Calif. Acad. Sci.) on Duncan<br />
Creek, at Silvester's ranch on the Middle fork of Cottonwood Creek, and on Dry<br />
Creek, at about the same stratlgraphlc horizon. Its atratigraphic range in this<br />
district ie from the lower or middle Paskenta group (Valanginian) to the middle of<br />
the Horsetown group (Bedoulian). In the McCarthy Creek district, as recorded by<br />
Stanton, its range may be somewhat more restricted, but it has been found in both<br />
Paskenta and Horsetown beds.<br />
JfopJflcW«er« anoen&t Anderson, a, sp,<br />
(PLIUI S3, FIFFUR 3, a», 3b: PEATN HI, FLJPIM 4]<br />
In the collection of the Academy of Xatural Sciences of Philadelphia there is a<br />
fragment of Hopteicrioceraa, related to H remondi (Gabb), but possessing much finer<br />
fiexuous costae, which are bundled on the dorsal border and have a section relatively<br />
much broader. It is No. 12BSS (Phila. Acad, Nat. Sci.), and although it has tie<br />
locality label the lithology, preservation, and association with other forms under<br />
tbe same number indicate that it was found in the Ono zone, either on Eagle Creek<br />
or on the Cottonwood Creak, near Locality 1353 (Calif, Aead. Sci.). The suture line<br />
ia similar to that of H. remondi (Gabb). It bears the same number as a small example<br />
of Crioeerat latum and also of Hoploerioceras remondi from the same place. The<br />
holotype has the following dimensions; length, 45 nun.; height, 23 mm.; width of<br />
whorl, IS nun. As seen on the periphery there are about 6 linear ribs to the centimeter.<br />
These are slightly flexuous and nearly normal to the curvature of the periphery.<br />
The suture lines are trifid, possessing long slender elements. No other example<br />
of this species has yet been seen,<br />
Hoplocrioceras mnlunium Anderson, n. sp.<br />
(Pl»t« 60, flcun* J, 4)<br />
Shell not large, coiling is first crioceratid, but later more openly, the whorl of<br />
the body chamber departing from the earlier coil and forming a short curved shaft,<br />
apparently not forming a hook; early coila not quite contiguous and gradually<br />
Spreading; section of the whorls .sub-quadrate, narrowing toward the rounded<br />
periphery; shell slightly excavated on the dorsal zone; costae beginning in a backward<br />
sinus on the dorsal zone, curving upward in eroding the umbilical border,<br />
slightly flexed on the side of the shell, somewhat swollen and often dividing on the<br />
doreal border, or a little below the middle of the aide on the septate portion of the<br />
shell; costae on the younger whorl nearly equal, but on the body chamber often<br />
showing intermediary ribs on the upper part of the side; all costae crossing the<br />
ventral zone without interruption, but slightly flattened; autuial characters not well<br />
shown, but the septum beginning with a siphonal saddle somewhat rectangular in