【摘要】 <正> 据文献记载,广西泥盆纪腹足类化石仅有Pleurotomaria (Euryzone) itys, P. (E.)de-phinuloides, (Schlotheim), Hormotoma sp.,Platyceras sp.。近几年来,笔者在鉴定地质队的标本时,发现广西泥盆纪腹足类化石相当丰富,广布于各种相区。目前共发现化石点26处(插图1),共17个属。这些腹足类多数生活在浅海陆棚地带,与底栖的腕足类、珊瑚共生,在象州型和过渡型相区化石比较丰富,南丹型相区化石较少。其层位分布见表1。更多还原

【Abstract】 The gastropod fossils described in this paperwere found from the Devonian strata at variouslocalities of Guangxi, consisting of 7 species and 7genera (including 3 new species and 2 indetermi-nate species). The localities and strata togetherwith the fossils contained therein are recognized as follows: 1. Liujing Member of Early Devonian Yu-jiang Formation in Wuhe, Yongning County: Mu-rchisonia cf. angulata Phillips, Meekospira sp.,Hormotoma sp. 2. Upper part of Early Devonian in Wuxu,Hechi County: Eotrachydomia hechiensis Y. T.Pan et Wei (sp. nov.). 3. Middle Devonian series in Shangfu, Hu-anjiang County: Straparollus (Philoxene) serpens(Phillips). 4. Lower part of Middle Devonian in Hu-angla, Luzhai County: Tropidodiscus nodocostatusY. T. Pan, et Wei (sp. nov.). 5. Lower part of Upper Devonian in Xi-ajia, Lingyun County: Eotomaria lingyunensis Y-T. Pan, et Wei (sp. nov.). Description of new species Tropidodiscus nodocostatus Y. T. Panet Wei (sp. nov.) (Pl. I, figs. 4, 5; Text-fig. 2) Small lenticular and symmetrical shell con-sisting of 5 whorls. Outer whorl large, incre-asing moderately in size toward the aperture, andembracing about one-third of the preceding whor-ls, with the greatest convexity near the umbilicaledge. Umbilicus moderately wide. Umbilical wallhigh and steeply inclined, with a subangular um-bilical edge. Dorsal carina usually very acute, onwhich the selenizone is situated. Whorl elongate-ly heart-shaped in section, with an acute edge onthe periphery. Surface ornamentation consistingof very thick, strong nodules and opisthoclinalcostae and growth lines. These characteristics dis-tinguish the new species from most other speciesof Tropidodiscus. Eotomaria lingyunensis Y. T. Pan et Wei(sp. nov.) (Pl. I, fig. I) Moderate-sized, low-spired, rapidly expand-ing gastropod with a selenizone situated on angu-lar periphery, and a blunt carina on the upperside of body whorl near suture. These characte-ristics differentiate the new species from Eotoma-ria delia (Billings) of Lower Devonian in NewYork State, U. S. A. Eotrachydomia hechiensis Y. T. Pan etWei (sp. nov.) (Pl. I, figs. 2, 8) Moderate-sized, low-spired, subglobular, ra-pidly expanding gastropod with 7 spiral rows ofnodules, among which 3 spiral rows on the slop-ing ramp are more strongly developed than the 4spiral rows on the base. The new species can bedistinguished from Eotrachydomia wenchuanen-sis (type species) of Middle Devonian in Wenchu-ang County, Sichuan by its absence of evidentspiral ridges.更多还原