ZONE OF ARIETITES OBTUSUS. 



51 



found, with their plant-like arms laid out in all directions, and generally coated with 

 ferric disulphide. The remarkable Liassic Dinosaurian Scelidosaurus Harrisonii, Ow., 

 so fully figured and ably described by my friend Professor Owen, E.R.S., in the Palaeon- 

 tographical Society's volume for 1859, was discovered some years ago by Mr. Samuel 

 Clarke, of Charmouth, in the dark shales of bed No. 8, above the mudstones. 



Fossils of the Zone o/ Arietites obtusus at Lyme Regis. 



Ichthyosarus platyodon, Conby. 

 Scelidosaurus Harrisonii, Owen. 

 Dapedius granulatus, Agass. 

 Pachycormus heterurus, Agassiz. 

 .ffichmodus Leacbi, Egerton. 

 Lepidotus rugosus, Agassiz. 

 Condostreus crassior, Egerton. 

 Arietites obtusus, Sow. 

 — Brookii, Sow. 



Arietites stellaris, Sow. 



— Sauzeanus, dfOrh. 

 Aegoceras planicosta. Sow. 



— Birchii, Sow, 

 Nautilus striatus. Sow. 

 Belemnites acutus, M.ill. 

 Pleurotomaria similis, Sow. 

 Inoceramus pinnseformis. Dunk. 

 Extracrinus Briareus, Mill. 



Foreign Correlations. — The zone of Arietites obtusus is developed in Germany, 

 although this Ammonite appears to be rare. Some of the specimens I saw in the collections 

 had been mistaken for Arietites Turneri and were labelled as such. In North Germany 

 argillaceous beds^ with Aegoceras ^^lanicosta, Sow., and Aeg. ziphus, Hehl., representing 

 this zone, are found resting on Arietenschichten in several localities, as near Harzburg, 

 Liebenburg, Hildesheim, Jexheim, Goslar, the Markoldendorfer Mulde, near Steinberg, 

 Falkenhagen, and the Empelder Ziegelei, near Hanover. 



In South Germany the zone is developed in Swabia, at the foot of the Alp 

 from Boll towards Randern. Arietites obtusus, Sow., is found likewise near Betzingen, 

 Balingen, and Aselfingen. 



Fossils from the planicosta-beds of North Germany ^=.tlie obtusus-beds of England. 



Arietites obtusus, Sow. 



— Sauzeanus, d' Orb. 

 Aegoceras planicosta. Sow. 



— zipbus, Hehl. 



— taraariscinum, Schlon. 

 Belemnites acutus, Mill. 

 Hydrobia cerithiiformis, Piette. 

 Turritella undulata, Benz. 

 Turbo paludinseformis, Schilbl. 

 Cryptaenia expansa, Soiv. 

 Dentalium Etalense, Terq. 

 Cylindrites fragilis, Bunk. 

 Pleuromya Hasina, Schilbl. 

 Goniomya heteropleura, Agass. 

 Pholadomya corrugata. Bunk. 

 Protocardia oxynoti, Quenst. 



Lucina problematica, Terq. 

 Modiola scalprum. Sow. 

 Avicula insequivalvis, Sow. 

 Gervillia olifex, Quenst. 

 Perna Pellati, Bumort. 

 Cucullsea Miinsteri, Ziet. 

 Leda complanata. Sow. 

 Lima gigantea, Sow. 



— pectinoides. Sow. 

 Pecten textorius, Schloth. 

 Plicatula spinosa, Sow. 

 Grypbsea cymbium, Lamk. 

 Waldbeimia cor, Lamk. 

 Spiriferina rostrata, Schloth. 

 Rbynchonella variabilis, Schloth. 

 Lingula Voltzii, Terq. 



