
JOURNAL OF PALEONTOLOGY, VOL. 34 PLATE 102 Murphy & Rodda MOLLUSC A OF CRETACEOUS ROCK, CALIFORNIA 841 deal of variation in the inflation and spire bigny), the type of Trajanella (Cossmann, height even in specimens from a single lo- 1909, pi. 2, figs. 16-18), but is more inflated cality, but the growth line characteristics and has a lower spire. Some specimens of are the same in all specimens. Anderson "Acteonina,> bellavistana Anderson and "A." (1958, p. 156) has recognized "Acteonina," berreyessaensis Anderson appear to be very californica Gabb from Thompson Creek, similar to the genotype. Yolo Co., and chose a specimen from this Large, accurately located stratigraphic locality as the "neotype" of A. californica collections will be necessary to obtain a Gabb. Anderson (1958, p. 152-159) has also more satisfactory solution to the taxonomic described seven new species: A. ursula and problem in this group. At present we do not A. ursulagorda from the same locality on feel that any of the described species can be Bear Creek, on the east side of the Sacra- used as an indication of stratigraphic posi- mento Valley; A. bellavistana from one mile tion except in a broad sense. North of Frazier Corners East of Redding; A. berreyessaensis from the same locality as Family APORRHAIDAE A. californica above; A. roguensis from Genus ARRHOGES Gabb, 1868 ARRHOGES CALIFORNICUS (Gabb) Phoenix, Oregon; A. colusaensis from the PI. 102, figs. 6,7 Peterson Ranch near Sites in Colusa Aporrhais californica Gabb, 1864, p. 128, pi. 29, County; A. yrekensis from Hagerdorn figs. 230 a,b. Ranch, Siskiyou County. It would probably Arrhoges californicus (Gabb), Stewart, 1926, p. be too much to expect that all these can be 363, pi. 21," fig. 15. considered as one species as the lower occur- Anchura (Arrhoges) californica (Gabb) Stewart, rence is upper Albian for specimens from Anderson, 1958, p. 165. the Bald Hills formation, and probably Shell small, spire about \ height of shell; Senonian (?) for A. ursula or A. ursulagorda. number of whorls about 8; ornamentation Yet examination of the collections fails to consists of narrow longitudinal ribs shal- show any obvious reason for the separation lowly concave toward the aperture and ex- of two or more species. The amount of vari- tending from just below the suture to the ation between specimens from a single lo- widest portion of the whorl, they number cality is as much as the variation among about 20 per whorl except on the body specimens of all localities. whorl where the number is reduced to 3 Trajanella californica (Gabb) closely re- more pronounced ribs on the back of the sembles the figure of T. amphora (d'Or- whorl with the apertural side covered by EXPLANATION OF PLATE 102 FIGS. 1—Cantharus occidentalis (Gabb) Apertural view of specimen 28637 U.C.L.A. Invert Paleo. Cat. XI. 2—Acteon sullivanae n. sp. Apertural view of the holotype, 28642 U.C.L.A. Invert. Paleo. Cat. X2. 3,4—Cylichna andersoni n. sp. 3, view of specimen 28653 U.C.L.A. Invert. Paleo. Cat. showing the shape of the shell: 4, apertural view of the holotype, 28652 U.C.L.A. Invert. Paleo. Cat. X2. 5—CUnura anassa n. sp. Apertural view of the holotype, 28641 U.C.L.A. Invert. Paleo. Cat. XL 6,7—Arrhoges californicus (Gabb). 6, apertural view of a small specimen, 28626 U.C.L.A. Invert. Paleo. Cat., showing spire and ornamentation of early whorls; 7, adult specimen, 28625 U.C.L.A. Invert. Paleo. Cat., showing body whorl and partially preserved wing, X2. 8,9—Paleosephaea sacramentica n. sp. 8, oblique view of aperture of holotype, 28638 U.C.L.A. Invert. Paleo. Cat., showing the three columellar plications; 9, view of specimen 28640 U.C.L.A. Invert. Paleo. Cat. showing ornamentation of shell. XL 10—Mesopuzosia colusaense (Anderson). Lateral view of specimen 28658 U.C.L.A. Invert. Paleo. Cat. Slightly less than natural size. 842 MICHAEL A. MURPHY AND PETER U. ROD DA callus, shell surface covered by fine spiral angulation; one or two secondaries may be lines with the two or three just below the developed below the lower angulation; the suture much stronger than the others; on surface of young specimens is covered by some specimens the longitudinal ribs are so fine lirae, in the adult the ornamentation is reduced as to form a reticulate sculpture; mostly covered with callus; number of growth lines are obscure on most of the whorls is greater than 5; suture linear, shell, but the outer lip is ornamented only faint; aperture narrow above, widening be- by growth lines; the first three whorls are low (anterior part unknown); in adult unornamented; wing large, as wide as body specimens the posterior digitation rises whorl, with posterior rostrum nearly as high along the upper part of the shell obliquely as spire; outer portion of wing thickened; and attached to the spire for about f the anterior canal moderately long and rapidly length of spire and then is free of spire and tapering from body whorl; inner lip smooth directed away from aperture; anterior digi- with light callus. tations not preserved; adult possesses tuber- Hypotypes.—The hypotypes, U.C.L.A. cule-like knob f of a turn back from the Invert. Paleo. Cat. nos. 28625 and 28626, aperture, apparently a callus deposit. were collected from locality 3465 on the Holotype.—The holotype, U.C.L.A. In- North Fork of Cottonwood Creek. Dimen- vert. Paleo. Cat. no. 28627 was collected sions of adult specimen: height 21 mm. from locality 3763. Dimensions: height (in- (incomplete—lacks first whorl and top of complete) 19 mm., spire height 9 mm. (in- anterior canal), height of spire 11 mm.; maxi- complete), greatest width (less apertural mum thickness of last whorl (not including canals) 12 mm. Paratypc U.C.L.A. Invert. outer lip) 8 mm. (including outer lip) 16 Paleo. Cat. no. 28628. mm. Remarks.—This species differs from the Remarks.—The specimen figured by Stew- genotype, T. distorta Gabb (1864, pi. 20, art (1926, p. 363, pi. 21, fig. 15) is here figs. 82,82a,b), in having three primary ribs designated as the lectotype of Arrhoges on the body whorl and a much smaller tu- californicus (Gabb). The hypotypes have bercule-like process. T. bicarinata (Gabb) been compared with this specimen through (Gabb, 1869, pi. 27, fig. 47; Stewart, 1926, the courtesy of H. Richards, of the Academy pi. 23, fig. 6) is shorter, wider and has two of Natural Sciences of Philadelphia who heavy carinae with no intermediate rib. loaned us the type lot. The lectotype is The trivial name is from Latin, three. "probably from the Siskiyou Mountains" (Stewart, 1926, p. 363). This species is very Genus GYRODES Conrad, 1860 similar to specimens in the U.C.L.A. collec- GYRODES ALLISONI n. sp. tion of A. occidentalis (Beck), the genotype, PI. 101, figs. 18,19,20 a Recent shell from the North Atlantic. Shell thin, small to medium size; spire This Cretaceous species is much smaller, has about g the height of the shell; number of shorter longitudinal ribs, fewer spiral lirae, whorls about 4; subangular shoulder and possesses two to three strong spiral ribs wide posterior tabulation; tabulation flat just below the suture, and has a slightly to very shallowly grooved; ornamentation longer anterior canal. of spiral lines, very fine on most of the whorl, and strongly developed on the pos- Genus TESSAROLAX Gabb, 1864 terior tabulation; growth lines fine but dis- TESSAROLAX TRINALIS n. sp. tinct; sharp double angulation at the edge PI. 103, figs. 1,2,3 of the umbilicus, band between angulations Shell small, moderately thick, spire about flat to depressed and nearly as wide at the \ height of shell; body whorl biangulate with umbilical opening; suture impressed; aper- two rounded carina-like spiral ribs at the ture elongate oval. angulations and a third midway between; Holotype.—The holotype and paratype, the upper rib is slightly stronger than the U.C.L.A. Invert. Paleo. Cat. nos. 28629 and lower ribs and all may be slightly beaded; a 28639, respectively, were collected at local- single secondary rib may be developed be- ity 3464 near the Gas Point road. Dimen- tween the posterior suture and the upper sions of the holotype: height 13 mm., height MOLLUSC A OF CRETACEOUS ROCK, CALIFORNIA 843 of spire 2\ mm.; maximum width of last last volution to be slightly flattened on the whorl 12 mm. posterior half of the whorl; aperture similar Remarks.—This species most nearly re- to the genotype but more elongate and sembles "Gyrodes" siskiyouensis Anderson columellar wall more curved; umbilicus (1958, p. 150, pi. 21, figs. 6,7) in ornamenta- elongate, narrow, eye-shaped slit; moderate tion, but has a more prominent shoulder, callus on the inner lip. and a flattened or slightly concave flank be- Holotype.—The holotype and paratypes, low the shoulder. The umbilical characteris- U.C.L.A. Invert. Paleo. Cat. nos. 28631, tics of G. siskiyouensis are not known. This 28632, 28633, respectively, were collected at species differs from other California forms U.C.L.A. locality 3763. Dimensions of holo- in the ornamentation of the tabulation. type: height of shell 24 mm.; width of body This species is named for Edwin Allison, whorl 17 mm.; height of spire 9 mm. Department of Paleontology at the Univer- Remarks.—A. stantoni n. sp. resembles sity of California, Berkeley. Lunatia avellana Gabb (1864, pi. 19, fig. 60) but does not resemble the plate of Stewart's GYRODES GREENI n. sp. lectotype of Ampullina avellana (Gabb) PI.
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