Tarrantoceras Stephenson and Related Ammonoid Genera from Cenomanian (Upper Cretaceous) Rocks in Texas and the Western Interior of the United States: Issue 1473
William Aubrey Cobban
1988年1月 · U.S. Government Printing Office
电子书
30
页
report评分和评价未经验证 了解详情
关于此电子书
Tarrantoceras, Eucalycoceras, Pseudocalycoceras, Sumitomoceras, and Neocardioceras are closely related genera of ammonites confined to rocks of middle and late Cenomanian age. Tarrantoceras, represented by T. sellardsi (Adkins) and T. flexicostatum, n. sp., was probably derived from Calycoceras (Gentoniceras) leonense (Adkins). Eucalycoceras appeared abruptly near the end of middle Cenomanian time and then disappeared until the middle of the late Cenomanian. The genus is represented by E. templetonense, n. sp., and E. pentagonum (Jukes-Browne). Neocardioceras, which was probably derived from Tarrantoceras, is known by the new species N. uptonense and N. laevigatum of early late Cenomanian age, N. minutum, n. sp. and N. sp. of middle late Cenomanian age, and N. juddii (Barrois and de Guerne) and N. densicostatum, n. sp., of late Cenomanian age. Pseudocalycoceras and Sumitomoceras, known only from the later part of middle late Cenomanian time, were probably derived from early forms of Eucalycoceras pentagonum. Pseudocalycoceras is represented by P. angolaense (Spath), and Sumitomoceras is known from S. conlini Wright and Kennedy and S. bentonianum (Cragin).
为此电子书评分
欢迎向我们提供反馈意见。
如何阅读
智能手机和平板电脑
笔记本电脑和台式机
您可以使用计算机的网络浏览器聆听您在 Google Play 购买的有声读物。
电子阅读器和其他设备
如果要在 Kobo 电子阅读器等电子墨水屏设备上阅读，您需要下载一个文件，并将其传输到相应设备上。若要将文件传输到受支持的电子阅读器上，请按帮助中心内的详细说明操作。
