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(1)on. ■New. a. I血sectivora. from■. Formation. in. KtlZuii. Upper. the Japan.. By. IIASEGAWA. yt)shikazu. several upper. Kuzuii. KISIIIDA. them. regarded. a. not. of. the E･. in this･paper･. Chimarrogale. and. na血ed. The. of them･ in the. description. any. give. from. S=IKAMA. dealt. are. species. new. T･. name. papers of MS is mentioned Kishida crass7･dentata however, these specimens, speaking, (1937a, 1949)･ Taxonomically is going so are homogeneous, that the author not groups, of two. shikama consisting to divide. into. them. The. recent. species. and. Formosa,. and. and Shikamainosorex of Anourosorex in Assam･ are distributed Anourosorex. two. a. of fossil. America,. N.. in the. is found. and. ParacryPtotis. to. is nearest. horizon. same. Upper. the. of. of. Pliocene. of. Pleisto-. Middle. the. of. China. South. Pleistocene. Lower. in the. found. was. species. nOV･･. gen･. genera. Shikamainosorex. Kansas,. as. by. collected Prefecture. Totigi. did. thoughhe. crassidentata, of Chimarrogale. in Japan.. cene. The. The. Dr.. cultural. author. offer. K.. KIYEIDA. the. course. of Zoology,. the. also. greatly. author. to. indebted. for. their. He. information N･. NAORA. unstinted. help CLASS. diagnosis. :-A. University･. Tokyo. the. and. of Geology･. advices. IMAIZUMI. aid in valuable insectivora･ recent. Mammalian. Agri-. Ornithology･. Museum National. Of enabト Ⅲe is of. the. Science. Soricidae gen.. densicingulata, shrew. guidance Professor. thanks. advice･. Shikamainosorex,. Generic. kind. the. Insectivora. FAMILY. :-Shikamainotorex. his. Of. Mammalia. ORDER. Genotype. the. Of Section and. SBIKAMA. for his on. Of. Dr･ H･ OzAKI. and. T･. suggestions valuable to Dr･ Y･ is grateful. study･ Museum, Science. acquire to Dr･ and. their. he. of Science,. of Mammalogy. this. of National. University. Museum,. for. Station,. for Also. disposal･. Faculty. Institute. the. Of. Experiment. ing. waseda. at specimen Institute, GeologlCal. Professor. to. University,. his. the. of. the. Of. National. Yokohama. the. Of. University･. thanks. sincere. S=IEAMA. T･. Professor. to. National. his. extends. lnstiture,. throughout section. Yokohama. lnstiture,. Geological his and TAKAI F.. is dedicated. Shikamainosorex. name. Geological. and. in. Formation. Once. china.. insectivora. of. specimens. as. large. as. nOV･. sp･. novI. ParacrMtotis. rex. Hibbard. with.

(2) 66. Y.. lower. dental. well. developed. 1, 1, 1,ユ;3; teeth. formula and. triangular.. condyle. This. ●ShikaJnainoso工.eX. incomplate. cal. lnstitute,. Yokohama. The. angle･. 12,. left. National. Figs.. ventral. ParacryPtotis. to. d￠nsicirLg111ata,. (Pl. ⅠIolotype:-An. brown, their cingulum white yellowish broad, Infracondylar notch quadrate.. Molars 'notch of obtuse is nearest genus. smooth.. Supuracondylar. obsolete.. Hasegawa. the. of. flibbard.. rex. nov.. sp.. 1-3) bearing. ramus. P｡-M3,. in Geologi-. Stored. University.. ゞ壬+. ､R■n. /J†〉. T<. ､( P. side. Ml. M2. c畠. 領 Lit. Af3 /. ′￣ー､ /-I-. I-'t. ⊥-+. ゝ. ＼＼. ′￣し. ＼. ヽ. ＼. β. aP. Y. ーー. ＼. ーーJ. n7f. dt. CP m￠d. prd hyd. end. pad. rf ■￣■. ￣ヽ. ′-. J ′. ′ノ. af. /. /. / / /. /. I/. C. ･Text. clusal condyle., condyle;. fig. view.,. 1.. Shikamainosoyex. B:. Buccal. view.,. Abbreviations: ap.,. angular. process;. mandibular bydリhypoconid; entoconid; about. x. 6. Lingual. drawing. afリarticular fossa;. rf” ramal ned.,. by. gen.. cs.,. metaconid;. author.. facet; dt.,. et D:. viewリ. process;. cpリCOrOnOid. foramen;. mat.,. toconid.. densIClngulata,. C:. nov.. mf.,. A:. Oc_. view. of Cリ. spicule;. coronoid. digastric. pad.,. sp.. Posterior. mental. foramen;. tubercle;. paraconid;. prd.,. end., pro-.

(3) on. New. a. florizon. from. lnsectivora. the. Pleistocens. :-Middle. in. Formation. Upper-Kuzuti. ; Shikama'-s. 67. Japan. Kuzuiian. Upper (1■952). ; Kuzuii. Formation. Kuzuii,. in Izuruhara :-Okada-quarry, Description anterior of Eolotype:-The IJOC.ality. Incisor. off, but with but its alveolus is lost,. of the canine. alveolus is also. individual. end. is broken. lost. the antrior under the premolar. p4. to. reaches but. part. is unicuspid,. part. its outer. to. and. ramus. Japan･ mature. of. Posterior. elongate･. M3.. of. it to have been show Perhaps the canine. premolar･. elongated. in site. large. lower. the. left. a. of. is present,. its alveolus a. of. part. P4-M3. Prefecture,. Totigi. greatly is. than. smaller. length. The＼greatest. side･. reduced. of. it,. A cingulum line of the puter side, is 2･5mm二 median crown, is lingual buccal base is present the and along of the tooth and broadest border at tlle pOSterio-buccal of the tooth which projects outwardly, is a little valley it is developed on lingual There the side･ while poorly is closely developed from the posterio-lingual edge of the cingulum which border the anterio-lingual with backwardly, the upon which. in contact′ is cusp. the. across. measured. concave. as of P4 is high is the 一argest Ml. developed From toconid. to. paraconid. are. the. rTled end. ー. protoconid. PQd. antrior The. the and. ryd. %. and. protoconid from the. to metaconid bending. A broad. the. ＼､観. 琴ン鴨. 司 jーー. .I. ノ ∼.-..... J. .. I;,.i). Text丘g. Lateral. and. condyle,. No.. 2.. Paracryptotis. occlusal. 27257.. rex. views,. (after. C.W,. the. Hibbard;. U.M.M.P.. Ⅲibbard). Part No.. 25172,. of and. left. ramus,. Poaterior. Ml-M3. view. pro-. occlusal. /Li''J/). 九k)hid. ”-2. P4. is especially well bypoconid･ the and. cingulum. hJd. prd. M了. set,. (. 敬 pTd. is. of. ＼. i5:. pgd. Ml. border. ′ー. 桝gonI-d. 巾らd. of. end. of tolerably. escarpments. made?mooth. Posterior. o土Ml･. paraconid. of the threeMolars･ the lower part of. between. the. the. Ml.. of. of.

(4) Y.. 68. is. surface deeper. than. the. part. the. of. a. quently. The. anterior. the. metaconid. to. of. the. of the the. the. The. to. part. is the. posterior. the. entoconid conse-. hypoconid. the. entoconid,. but. its shape. is bestdeveloped. under. among. metaconid high as. hypoconid,. the. of. is. the. of. part. posterio-buccal. seen. as. and. stretches. entoconid. paraconid. the. is rounded,. is. the-paraconid. entoconid･. posterio-lingual. basill is. developed. well. and. entoconid. margin and. front. the. metaconid. to. metaconid. metaconid,. to. stretches. the. paraconid･. The. paraconid･. the. separating distance from. The. from. that. than. higher. valley. in M2･. than. larger. A. seen.. Hasegawa. and. metaconid. is quaderate different from the M2. of. the to. near. the. A. Ml.. prototonid.. The. breadth. from. the. paraconid. and. the. of. posterior. is reduced, between the. opens. than. follows. in. the. from. and the. the. of. of the. entoconid･ The undeveloped･ further disappears, and The′. a. is. metaconid teeth. the. of. 5.8. is larger. HIBBARD.. length. of. mental. surrounding. the. a. large,. considerably. MI. 1.6×2.4. M2. 1.4×1.8. M4. 1.1×1.5. foramen foramen. and. developed is. is. of is situated. is 5.7. rex. than. are. situated depressed, oval,. a. as. the. hypoconid. its. situated is subtrian-. the. of. anterior. is. which. middle. 5135). Paracrypto-. the. and foramen. mandibular fossa, ramal. in. &. that′to. beneath. The. paraconid･ γentral border. the. of. wall. 1.4×1.3. the. under. (P.. P4. widely. more. and. The. reaches. gular,. is. paraconid The heights. 7.0. and. Ⅵ7idth. ramus. beneath. part. is. Dimensions. P4-N3. of. I〉. margln. much. the. that. metaconid･. bypoconid･. and. II. area. entoconid and. II. The. cingulum. than. so. lower. the. entoconid.. MI-M3. of. Maximum. rex. the. higher. hypoconid. paraconid. length. Ditto. tis. to. the. to. metaconid. is not. mm:. United. Thc. the. somewhat. molars, hence. border. Ml,. the. metaconid are. metaconid. is smallest. valley higher. than. smaller cingulum distance. the. M3. and. posterio. of. ramus.. The. digastrict like. swollen. a. is cleary The visible. line, lower the and straight. tubercle. short. coronoid. border. upper. and. is obtuse,. spicule. of. it is. COnCaVe.. The margin. longitudinally. is curved. ramus. ascending of it is. straight,. from. the. and upper. margin. The c､oronoid･ supracondylar developed. The upper and well facet is of the ventral margin concave. triangular. in. the. in outline.. same. The. inner. the. of. Ⅲ. is. forwardly. notch edge convex. direction. angular. and side. of ramal is obtuse･ of the condyle downwardly, The. inwardly.. The. posterior. it is tolerably. of. fossa. to. The. the. γentral is broken process. border. upper. condyle is very flat.. while border. grooved. is. rugose. The. lower. Paracryptotis. of the condyle the- base off, but. rex. is is.

(5) bn thinnest. a. and. New. insectivara. of the. veakest. Lengtb. from. the. those the and. end. large. &. ELLERMAN nIBBARD. M.. ventral. size. be. to. base. the. of. Paracrhtotis. with. Many. like. are. characteristics For are distinct･. H.. rex-. T.,. 1937a:. and. in. 44,. No.. 1937b: Imp.. Acad. 1949:. -----,. the. Limstone Ser. 1952:. R-ep. Yokohama. of. Short Kuzuii. the. of. of. Palaearctic. Re予road. and formation. Pal.加匝chigan. Univ.,. the. Mus.. Cont. No.. Selected. Checklist. lnsecivtores. γol. 27,. Caves. 口niv.,. 7). Kansas,. S瓦艶AMA. vol.. 1951:. Mammals. The. ヾJour. Paleo.,. -. compared. forms.. two. the. of. ScoTT,. County,. 3). 6). are.. margln. posterior. the. mm.. facet‥..‥..…..‥.........…...….2.2. articular. is. 1950;. C･W･･ 1953:. -. in. ramus. 69. rex.. Meade. 5). the. of. LiterattLreS. 4). i to. the. in Japan. detailed instance, features of ParacryPtotis, but血any tis distinguished P4 from the the Paracrypioiis, especially, at cingulum Also, in general, is more Ml. the ramus than roundish slender and. Paracrhtotis. 1) 2). of. of. ………‥…‥‥………………..……‥‥………‥‥--13 to process coronoid. tip. lower. the. of. the. of. Forma･tion. Dimensions. alveolar. Remarks:-Shikamainosorex because. Kuzuii. process.........................･･.･････.･･･････････････-･････････････････････7･5 length at the inher side of condyle････-･･-･･･-･.-････--4-. Maximum Breadth. tip of. the. the Upper. ramus.. process.. of condylar Distance from angular. from. Fauna,. Rexrdad. Indian from. Fox':. VIII,. vol.. Upper. Mammals･. Pliocene. No･ of. Canyon, 6･. Kansas. ;. 1.. Notes. the. on. During. the. Excavation. Year瞥1931. to. Osq￣siferous Fissures of the 1936; Jour. Geol. SQC. Japan.. 524.. Ossiferous Tokyo, The. Fissure. Kuzuii. Fissure. Deposits. of. Kuzuii,. Totigi. Prefecture;. Proc.. XIII.. Vol.. Ossuaries Deposits,. Geological in Kuzuii,. and. Totigi. PalaeontologlCal Prefecture;. Studies. S°i. Rep.. of. Tohoku. ⅠⅠ,γol. XXIII. The. Japanese Nat.. Univ.,. Quaternary, Sec.. II,. Its Outline No.. 1.. and. Historical. Review,. S°i..

(6) El(PlanatiorL. Of. Tller Plate Shikamainosorex Fig･. 1･. Occlusal. Fig･. 2･. Buccal. Fig･. 3･. Lingual. view. XII,. ･Sbows. densicingulata at. view view. Plate. of. of. -teeth. holotype. bolotype.. (P4-M3) .×.9.5.. ×9.5.. gen･ of. et. bolotype... sp･. nov･. ×10.5..

(7) EASEGAWA. :-New. Hasegawa. photo.. lnsectivora.. Sec.. ⅠⅠ.Plate. XII.

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