LOWER CRETACEOUS DEPOSITS CALIFORNIA AND OREGON

description of species 219
plain or polished, ornamented only by a few extremely faint undulations. The
outer, or final limb, which is in places very much broken, had one or more constrictions,
or internal riba, which do not seem to have been visible on the external surface;
one or two such interns! ribs seem to have existed, though in much less degree on tbe
middle limb."
The holotype of this species is in the museum of the Academy of Natural Sciences
of Philadelphia and was loaned to the California Academy of Sciences for comparison
with others found at tho type locality. Three good examples were found in the
Perrin zone at Locality 1608 (Calif. Acad. Sci.) associated with Cleanicertu lecontci,
Phyllcccrov tkenaae, and other species. According to Gabb (1860a, p. 127), this
species was found with Ptilaieuthis Jolialu-t and a specieB of crustacean. Gabb's
holotype probably came from Hulen Creek, near the locality mentioned. It has not
been found at any other place.
Hamulina d'Orbigny
Genotype, Hamulina aubat/lindrica (d'Orbigny)
Hamtilina alder sona Anderson, n, sp.
[Plate IS, fijura 3, 2s)
Shell of medium size, limbs moderately separated, straight, finely costate with
major and miner coatae; section of each limb subcircular; smaller limb septate, the
septum resembling that of the genotype; costae on the smaller limb fine, rounded,
oblique, separated by wider interspaces; major costae faintly tuherculate on the
side, bearing spines on the ventrolateral and dorsal borders; on the smaller limb,
eight to ten finer costae intervene between the major, non-tuberculate costae; on
larger limb, costae trituberculate and occasionally epinose; minor coatae bearing no
tubercules. On the larger limb the costae are oblique near the bend but become less
so near the middle and at the extremity of the body-chamber. The holotype of thia
species was obtained at Locality 1343 (Calif. Acad. Set.) on Alderson Creek, about
2 miles south of Ono, Shasta County, at a horizon about 200 feet above the Argonaut
zono. It resembles Hamulina lorioli IThlig in its circular section, in its abrupt
bend, by which the two limbs become nearly parallel, and in ita captation, which on
the smaller limb ia oblique, becoming more nearly normal on the larger limb. In the
present species, however, the smaller limb bears a double row of elevated apinea on
the central borders and on the dorsum, with evidence of having had lateral tubercules
on the major coatac. The holotype (Calif. Acad, Sci. type Coll.) haa the following
dimensions: total length, 112 mm.; width between limba, 12 to 16 mm.; maximum
diameter of body-chamber, 22 mm.; maximum diameter of smaller limb, 12 mm.
Anahamulina Hyatt
Anahamulina veeperlina Anderson, a. sp,
{PUtftJQ, fifura 3, 3»)
Two examples of this specica, consisting for the most part of the body-chambera
only, were found at Locality 113 (Calif. Acad. Sci.) in the Hamlin-Broad zone, in
the upper part of the Paskenta group. The shell is of moderate size, hamitid in its
general aspect, closely costate, tbe costae on the two limbs being dissimilar in
both ze and direction; costae rounded, with equally broad and rounded interspaces;
costae on larger limb crossing it at nearly right angles to its dorsal border, in part
branching into two or three divisions below the middle of the side and occasionally
at higher points; costae bearing elongated nodes at points of division; costae on
.'•mailer limb oblique, inclined strongly forward; in part branching into two or three