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Textfig. 14. Musashia (NiPPonomelon ?) striata
(YoKOYA=A), restored, × 1･
1)埼玉県秩父郡皆野町大淵 2)同郡小鹿町野岩殿沢 3)三重県一志郡久居町榊原
* OTUKA's kamakurensis.
(pl. 14,丘g. 3) from Sakakibara, Hisai‑macbi, Ichishi‑gun, Mie Prefecture3) for comparison, he did not give any description of it. The writer selected the Chichibu specimen as the type of YoKOYAMA's striata though it is very fragmen‑
tary.
Original Description : megaspira Sow. hitherto
fossil (YoKOYAMA, Foss.
pl. ll,丘g. 18)* is smooth,
HThe shell of Voluta found either livind or
Miura Peninリ p. 46,
save strong longitudi‑
nal plicae. But the examples now under consi‑
deration are splrally and closely striated, the striae golng over the plicae also.
Remarks: Thi畠species may be character‑
ized by
angulated shoulder, medium size, strong and ridge like axial folds, crossed by numerous radial striations, and relatively bigb splre.
Protoconcb unknown. There may be 4.5‑5 post‑
nuclear whorls, and subsutural band absent.
Columella plaitりnknown but probably allied to those of tokunagai. The specimen from 6hara
(Pl,15,figs. 1, 2〕 is relativelyfine, with four whorls, and 16 axial folds in penultimate whorl, which are inclined to run oblique to sutural line above shoulder of penultimate and ultimate whorls. This characteristics may indicate its relationship with Miopleiona.
System and Evolution of Japanese Fulgorarid Gastropdda 103
Referred
specimens: NSMT}‑K 164, 597 (6specimens)
collected byOGAWA from the Nenokami bed of Chicbibu basin. NSMT‑P‑251 from the Miocene bed at 6hara･ Nima‑machi, Nima‑gun, Shimane Prefectu,e (Pl.15, Bg･ 1,
2)1)･
A shell (GIYU) collected by T･ UcHIDA from the Kanomatazawa bed at Kaiseki‑zawa, east of Sbionoyu, Shiobara‑machi, Shioya‑gun, Tochigi Prefecture2)･ A shell(GIYU)
collected by the writer from the Nukuda bed at Tamoto, Anan‑cho･ Shimoina‑gun･ Nagano Prefecture (Pl･15,触s･
3, 4)3).A small shell (G'lYU) collected by S･ HIROISHI from the Togari bed at Hane, Mizunami‑City, Gifu Prefecture4)･ Four shells (GIYU) collected by S. YAMA‑
sⅢITA from the Kaisekizan bed at Azzaka, Misato‑mura, Age‑gun, Mie Prefec‑
ture5'･ A small shell
(GIYU)
from the Kaisekizan bed, north of Ago, Misato‑mura, Age‑gun, Mie Prefeciure6)I A
shell with the last whorl and two whorls
of spire (GIYU) collected by S. YAMASⅢITA from the Kaisekizan bed at
Yanagidani･ Misato‑mura, Age‑gun, Mie Prefecture LPl. 15,fig. 517). IGPS cat.
no･ 72331 collected by HAYASI{I from the Miocene tuffaceous sandstone bed at
人
Odo, Saigo‑mura, Nasu‑gun, TochigiPrefdcture8',I last whorl and two wh.rls
of splre With 17 radial ribs on penultimate whorl and 27mm wide at last
wborl･ Ⅰ､GPS cat･ no･ 61385 collected by K. HATAI from the Kadonosawa bed at lcbinohe‑machi, Ninobe‑gun, Iwate Prefecture9). IGPS cat. no. 64410 coレ 1ected by K･ HATAI and S･ NISIYAMA from Oido, Motowakuya‑mura, T6da‑gun, MiyagiPrefecturelO'･ NSMT‑P14=75, 612 collected by TAKIMOTO from the Tempizan bed a Sukegawa, Hidachi City, Ibaraki Prefecturell).
Geological Horizons: The Nenokami bed of the Hikokubo Group; Oligo‑
Miocene, D‑E･ The Kanomatazawa bed ; middle Miocene, F3･ The Kaisekizan bed of the lcbisbi Group; early Miocene, F2･ The Nukuda bed of the Tomi‑
kusa Group; early Miocene, F2･ The Kadonosawa bed; early Miocene, F2･
The TemplZan bed;
probably latest Miocene, G.
Musashia (Nipponomelon?) densicostata sp. nov.
ウネヒタチオビ(新) (Pl･14,丘gs.2, 3)
1962･ Fulgoraria tokunagai (KANEHARA), KAMADA (pars). Pal. Soc. Jap. Spec.
Pap･, no. 8, p. 172, pl. 21,fig. 4,
1) 2) 3) 4) 5) 6) 7) 8) 9) 10) ll)
島根県連摩郡仁摩町大原
栃木県塩谷郡塩原町塩ノ湯東方貝石沢 長野県下伊那郡阿南町田木
岐阜県瑞浪市羽根 三重県奄芸郡美里村足坂 同郡同村安子
同郡同村柳谷
栃木県那須郡西郷村大戸 岩手県二戸郡一戸町 宮城県遠田郡元涌谷村追戸 茨城県日立市助川
104 ､T. SIiIKAMA
1964. Fulgoraria cf. striata (YoKOYAMA), KANNO･ Sci･ Rep･ Tokyo Kyoiku Dai･
gaku, sec. c, no. 81, pl･ 2,丘g1 16･
IIolotyPe: TUE‑G‑KM 1260, collected by S･ KANNO from the lower Sanke‑
betsu bed at a river cliff of Kotanbetsu, Tomoe‑gun, Rumoe, Hokkaido･】) Diagnosis: Shell medium size, well inflated, thick and with very eminent axial folds wbicb are keeト1ike, broad and intercalating narrow interspacs･
There are developed numerous radial striations,
ど
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tL :
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‑/Text丘g. 15.
∫
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Musashia
(NiPPonomelon?) densicos‑
tata sp.nov‥ restored, × 1.
wbicb aross axial folds. Subsutural band absent and suture is rather deep. Postnuclear whorls probably 4‑5 in number and protoconch rather small. Columella plaits unknown.
Remarks: This species is rather related
with the American species oregonensis or
u)eaueri in dense structure of axial ribs, but is clearly distinguished from them by straight running of ribs. No such forms with appress‑
ed and dense ribs are known among Japanese
species.
Referred
specimens: TUE‑G‑K Loc･ 46,reported by KANNO aS Cf. striata form the Takinoue bed on the left bank of the Yubari River.2) KAMADA's coll.no. 254 from the Honya bed at Hieda, Sbimokaziro, Ena‑machi, Iwaki City, Fukusbima Prefecture･3)
Geological Horizon: The lower Sankebetsu bed of the Takinoue stage; early Miocene, F2･
The Takinoue formation; early Miocene, F2.
The Honya bed of the Yunagaya Group; early Miocene, F2.
Musashia (Miol?leiona＼indurata (CoNRAD, 1849) ワダチヒタチオビ(節)
1849, Rostellaria indurata 1909. MioPleiona indurata
CoNRAD.口.S. Explor･
(CoNRAD), DAlノL･ U･S･
･35, pl. 18,丘g. 5.
1942. MioPleiona indurata (CoNRAD), WEAVER･
pp･ 491‑492, pl･ 94,丘gs･ 5, 8, 131
1963. PsePhaea (MioPleiona) indurata (CoNRAD),
no. 419, pp. 42‑44, PIT 7,figs･ 1‑ll, pl･ 8･,figs･
1 2 3
北海道留萌苫前郡古丹別川流域 夕張川
福島県磐城市江名町下神自
Exped. Geolリp･ 729･
Geol. Surv. Prof. Jap., no. 59, p.
univ. Wash. Pub. Geol., vol. 5,
MooRF:. Geol. Surv. Prof. Pap., 1‑5.
System and Evolution of Japanese Fulgorarid Gastropoda 105 Holotype: USNM 5908 from Astoria, Oregon, U･S･A･
Original Description: LL Subfusiform, with oblique, curved, rounded ribs, whorls constracted or narrow
ments of casts. The lip does
Remarks: MooRE Writes,
has strong axial ribs; about de且ected near the suture and
toward
,the suture, The specimens are frag‑
not appear to have been greatly expanded.
"P. indurata is moderately thick shelled and 18 to 21∴per whorls. The ribs are slightly
are separated by interspaces as
wide to slightly wider than the ribs. There are faint traces of splral lines on patches of well preserved shell, especially on the earlier wborls･り Shell medium sized, high spired and with丘ve postnuclear whorls. Protoconcbノprobably small sized.
Suture deep and subsutural band absent. Shoulder a little angulated. Axial ribs ridge‑like, stout, dense and oblique to sutural line. Columella plaits unknown.
GeologLCal I7orizon : The Astoria formation ; middle Miocene.
Musashia
(ML'opleio21,a)
oregonensis (DALL, 1909) オレぜシヒタチオビ(節)1909. MioPleiona oregonensis DAL‑L. U.S. Geol. Surv. Prof,
,PapリnO. 59, pp･ 35, 36,
pl. 18,丘gs. 3, 7.
1931. Psephaea prevostiana (CROSSE)甘arl 0regOnenSis (DALL), GRANT & GALE･
Mem. Sam Diego Soc. Nat. ⅢistりVOl. 1, p. 634, pl. 27,丘gs. 6, 10.
1944, MioPleiona oregonensis DALL, KEEN & BENTSON. Geol｡ Soc. Amer. Spec.
PapリnO, 56, p. 171.
HolotyPe : USNM 153894.
Original Description: 〃She11 rather thin for its size, subovate, with about six whorls, the apICal whorls rapidly diminishing; nucleus small, its characters unknown; subsequent whorls with arcuate rounded ribs and wider interspaces, the ribs numbering about 14 on the penult and 20 on the last whorl ; surface otherwise smooth except for incremental lines, the'ribs feebler
on the last whorl; body rather turbid, the suture distinct, not appFeuSSed, the whorl in front of it sometimes showing an obscure marglnal ridge or sligl一t tabulation; strength of the ribs variable in different specimens; aperture semiovate; sulcate at the posterior commissure; pillar
straight,
with onestrong and one feeble plait about the middle of it, rather outer lip thin, slightly reflected, produced in the adult at missure. Length of largest (but imf)erfect)specimen,
restored smaller tyye specimen, 110mm; of aperture,
widely separated ; the posterior com‑
about 160mm; of
68mm;ねaximum diameter, 45 mm.
Remarks: This species is characterized with its smooth surface, vaulted whorls, relatively low splre, Small sized protoconch and coarse axial ridges･
There are丘ve postnuclear whorls and two columella plaits on last whorl.
Axial ribs also run oblique to suture line,
106 T. SIiIKAMA
I
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