Attribution of ammonites from Jurassic stratotypic sections in England

Abstract

A characterization of a collection of ammonites from type sections of the Jurassic system of England is given. The collection was assembled in the early 20th century and is held at the Department of Historical and Dynamic Geology, St. Petersburg Mining Institute. The diagnosis of ammonite forms made in the early 20th century has been revised and refined. The collection includes the following specimens: Psilloceras eruatum Phillips (old name Psilloceras planorbis Sow.), sinemur, locality Redstock; Gleviceros victoris Sow. (old name Oxynoticeras victoris), bluenemur, Redstock; Androgynoceras capricornus Schl. (Aegoceras capricomis Schl.), Lower Plinsbach, Sharmu g; Echioceras regulare True.-W. (Ophioceras raricostatum Zief.), lower Leias, Lyme Regiers; Acanthopleuroceras valdani (Aegoceras capricomis Schl.), lower Plainsbach, Charmouth; Soninia sp. (Sonninia sp.), Middle Jurassic, Bristol; Witchellia laeviusculata Sow. (Witchellia sp.), upper Lower Bajos, Bristol; Ludwigia Murchisoni Sow. (Cosmogyria), Lower Aalenian, Bristol; Euaspidoceras ex. gr. perarmalum Sow. (Aspidoceras per am atum Sow.), Lower Oxford.