LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON
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DESCRIPTION OP 8P£CIE8 201<br />
in older stages; costae of two kinds, major and minor; major costae tritubaroulate,<br />
with one row on each aide of the siphonal line, apinose, with slender elevated apinea;<br />
the two other rows of tubercules low and rounded, lower row transversely elongate;<br />
minor costae finer, non-tuberculato, rounded; there are normally five between each<br />
pair of major costae; section of whorl broadly elliptical, higher than brood; suture<br />
tine not shown.<br />
The holotype (Calif. Acad. 3oi. type Coll.) waa found at Locality 166$ (Calif,<br />
Acad. Sci.) on Duncan Creek, a mile above the County road, in a calcareous concretion<br />
embedded in sandstone overlying a local conglomerate. It belongs to the group<br />
of Criotcrat nolani Kilian, being somewhat closely related to the form figured by<br />
Kilian (1910, pi. 4, figs. 3a, 3b) under this new name.<br />
This specimen was found with the preceding species and with Neoeomite* rueselli<br />
nov., Lytaeeraa ef, irtwfci nov., Pleuromya papyr&cea Gabb, and various ether forms.<br />
A fragmentary but good specimen of SpUieerag, closely related to ducafe<br />
(Matharon), was obtained from a block of limestone lodged in the conglomerate<br />
beneath tbe sandstone.<br />
Crioserai duncanenut is doubtless related to Crioceras latum Gabb but differs<br />
from it in the relative width of coil, the whorls being less widely separated and the<br />
minor costae being more numerous. Both forms occur at thia locality.<br />
HEMiHOrLrriPAB Spath<br />
HopUicrioccra* remandi (Gabb)<br />
(PkLa 63, ftfUTM 1. 3, ], slrts 19, Scum 1, 3)<br />
Crioter aa (? Aneyloceroa) Remondi GABB, Paleont. Calif., vol. 1, 1854, p. 76, pi. 14,<br />
figs. 24, fcia; North fork of Cottonwood Creek, Shasta County, (not Aneyteeeras<br />
sp. mdet. pi. 16, fig. 30).<br />
Aneyloceraa Remondi GABB (in part), Paleont. Calif., vol. 2, ISM, p. 138, pi, 23, fig. 17.<br />
This species appears to have been much misinterpreted not only by later writers,<br />
but by Gabb himself; other species, and even genera, have been included under the<br />
name. The lectotype (probably the holotype) waa token by Gabh to the Academy<br />
of Natural Sciences of Philadelphia where it still remains, It was loaned to the California<br />
Academy for examination and illustration. It beam no distinctive label but<br />
is contained in a tray with other specimens labelled "Ancyloecros Remondi." Some<br />
of these specimens do not belong to this species, The locality of discovery is not<br />
definitely given, but the matrix and associated species in it indicate a locality near<br />
Ono, probably in the Ono zone near the base of the Horsetown group, where they have<br />
all been found.<br />
The species seems to hetong to the group of Crioceras laemuaeulum von Kdaa.cn,<br />
which Spath (1924, p. 73) includes in bis genus Hoploerioceraa.<br />
The holotype is not well illustrated by Gabb's (ISM, pi. 14, fig. 24) drawing, but<br />
the characters of the spcciea are better shown in the photographic illustrations here<br />
given. The costae are fascicled on tho dorsal border, arising from elongated bullae<br />
in ita younger stages, which disappear with the growth of the shell.<br />
According to Gabb, the<br />
"ribs are often diehotomous, and occasionally, though rarely, anastomose near<br />
the dorsum (vantor). In one esse, remains of a few dorsal spines were observed."<br />
This reference to "dorsal apinea" should be understood to refer to tubercules on<br />
the veotro-latcral angles, not true spines.<br />
These tubercules are indicated in bis figure and arc seen on the lectotype. They<br />
disappear when the shell attains a diameter of 60 nun. or leae. In section the whorls<br />
are narrowly olliptieal, the sides rounding abruptly on the dorsal border, but sloping