LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON

146 lower chetaceous deposits ijf california and oregon
others have sinco been collected. The Species occurs at other horizons in this group,
extending from its base to near its top. Unfortunately, the exact locality of the
holotype is not yet known, although it is believed to have boon found in the upper
part of the Paskenta group in the Cottonwood district, Shasta County, from which
fragments have been collected. In actual diameter, though not in weight, this ia tho
largest example of Lytoceras yet seen from the Lower Cretaceous of California,
although fragmentary specimens indicate larger individuals. If the body-chamber
to the extent of half & whorl were restored to the holotype, its total diameter would
be at least 26 inches.
The costae of this specimen show crenulations similar to those noted by Stanton on
the form figured by him. Another example in the Museum of Paleontology, University
of California, about 7 inches in diameter, shows the same characters. This
species differs from moat of the following in its more robust form, in its more restrained
sculpture, and in the cross-icction cf its whorla. The form figured by
Whiteaves (1884, pi. 27, fig, 1) under the name of "Lytocera* boteaj" Trask" may
represent this species. As it was obtained at Bearskin Bay, north shore of Skidegate
Inlet, it may have come from the AueWIa-besring beds of that locality. In form and
ornamentation this species is not unlike Lytoccraa liebigi (Oppel) from the Tithonian
beds of Moravia.
Lytoctras salurnale has a stratigraphie range almost throughout tbe Paskenta
group in its type district, and has been found in the Cottonwood district at various
levels in the same group. It has not been found in Knoxville beds at any place.
Lijtoceras traski Anderson, n. sp.
(Phis IS, ifaim 1,1; pht* IT, fiture 1)
Mature shell of moderate size, diaeoidal, somewhat robust, intermediate in form
between L, saturnale and X. bate*i; section of whorl subcircutar, a little higher
than broad, narrowing slightly toward the periphery; surface marked by both major
and more numerous minor costal lines; major costae appearing only at intervale of 10
to 12 minor costae, arising aa thin, prominent threads with broken edges.
This species appears to belong to the group which includes Lytocera* anisoptychum
Uhlig, from the Wernsdorfer beds, although it seema to have fewer and more prominent
major costae, not showing the "crinkley" character of the latter form. It also
resembles Lyt octroi exotieum (Oppel) somewhat, although this resemblance may be
only in its ornamentation. A few shallow constrictions appear at irregular intervals
on tbe septate portion of the whorl. The holotype (Calif. Acad. Sci. type Coll.)
has the following dimensions: greatest diameter, 125 mm.; width of umbilicus,
50 mm.; height of whorl, 46 mm.; width of whorl, 43 mm.; umbilical ratio, 0.4:1.
The sutural lines are similar to those of L. bateai (Trosk), as illustrated by Gabb.
The holotype was found at Locality 1347 (Calif. Acad. Sci.) north of Roaring River,
not far cast of Mitchell Creek, In the Cottonwood district, associated with Lylocera*
argenauiarum, Gabbioceraa anpulatum, Phyllocera* onoense, and Parahaplitoide*
cerronensit, ia the Argonaut zone. Its usual occurrence is in the lower part of the
Horsetown group. In tho Cottonwood district it occurs lower, but is not abundant
in lower strata, occurring sparingly in the upper part of the Paskenta group. The
species is represented by eight or more specimens in the collections Df tbe California
Academy of Sciences.
Lytocera* aulavum Anderson, n. sp.
(Plate 11, fieura 1, 3, 3, t)
This species somewhat resembles Lytoceras saturnalc in form, although it is less
rob oat, and the resemblance is chiefly in the surface markings. In section of whorl