ZONE OF LYTOCERAS JURENSE. 



145 



Pecfen Wickensis, Wright. 

 Goniomya angulifera, Sow. 

 Pholadomya fidicula, Sow. 



— obliquata, Phil. 



Monotis substriata, Milnst. 

 Gresslya peregrina, Phil. 

 Gervillia Hartmanni, Goldf. 

 Pinna cuneata, Bean. 



Cucullaea cancellata, Phil. 

 Lingula Beanii, Phil. 

 Rhynchonella cynocephala, Rich. 

 Discina reflexa, Sow. 

 Terebratula trilineata, Youwj ^ Bird. 

 Glyphaea Birdii, Bean. 



— n. sp. allied to G. rostrata. 

 Heterocidaris Wickensis, Wright. 



No. 5, hard argillaceous shales with layers of nodules, which lie at the base of the 

 sand, and rest vipon the Alum-shale. In this band, however, are found certain species 

 of Amraonoida not met with in any other rock on the Yorkshire Coast, and they are all 

 leading fossils of the zone of Lytoceras jurense, Ziet., as 



Lytoceras jurense, Ziet. 

 Harpoceras insigne, Schiibl. 



— variabile, d^Orbig. 



— Aalense, Ziet. 



— striatulum. Sow. 



Monotis substriata, Miinst. 

 Goniomya angulifera. Sow. 

 Discina reflexa. Sow. 

 Lingula Beanii, Phil. 

 Rhynchonella Jurensis, Qiienst. 



The dark-grey calcareo-argillaceous nodules rest on the clays of the Upper Lias, 

 or the true Alum-shale containing Stephanoceras crassum, StepJi. commune, Steph. 

 fibulatum, Leda ovum, and Trigonia literata. 



Fossils of the Zone of Lytoceras Jurense. 

 Reptilia. 



Vertebrae of Ichthyosaurus. 



Pisces. 

 Teeth of Hylodus. 



Lytoceras Jurense, Ziet. 



— hircinum, Schloth. 

 Harpoceras insigne, Schubler. 



— Comense, von Buch. 



— Aalense, Ziet. 



— discoides, Ziet. 



— Thouarsense, <^'0r6. 



— striatulum. Sow. 



— radians, Reinecke. 



— Eaquinianum, d'Orb. 



— Levesquei, d'Orb. 



Cephalopoda. 



Harpoceras Leckenbyi, Lye. 



— variabile, d'Orb., var. Beanii, Simp. 



— variabile, d'Orb., var. dispansum, 



Lye. 



— obliquatum. Young S( Bird, the 



aged form of variabile. 

 Nautilus latidorsatus, d'Orb. 

 Belemnites compressus. Volts. 



— tripartitus, Schloth. 



— irregularis, Schloth. 



— Nodotianus, d'Orb. 



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