ZONE OF LYTOCERAS JURENSE. 



145 



Pecten Wickensis, Wright. 

 Goniomya angulifera, Sow. 

 Pholadomya fidicula, Sovj. 



— obliquata, Phil. 



Monotis substriata, Miinst. 

 GressJya peregrina, Phil. 

 Gervillia Hartmanni, Gold/. 

 Pinna cuneata, Bean. 



Cucullaea cancellata, Phil. 

 Lingula Beanii, Phil. 

 Rhynchonella cynocephala, Rich. 

 Discina reflexa, Sow. 

 Terebratula trilineata, Toung ^ Bird. 

 Glyphsea 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 upon the Alum-shale. In this hand, however, are found certain species 

 of Ammonoida 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, Schilbl. 



— variabile, d'Orbig. 



— Aalense, Ziet. 



— striatulum, Sow. 



Monotis substriata, Miinst. 

 Goniomya angulifera, Sow. 

 Disciua reflexa, Sow. 

 Lingula Beanii, Phil. 

 Rbynchonella Jurensis, Quenst. 



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

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

 fihulatum, Leda ovum, and Trigonia literata. 



Fossils of the Zone of Lytoceras Jurense. 

 Reptilia. 



Vertebrae of Ichthyosaurus. 



Pisces. 

 Teeth of Hybodus. 



Lytoceras Jurense, Ziet. 



— hircinum, SchVdh. 

 Harpoceras insigne, Schubler. 



— Comense, von Buck. 



— Aalense, Ziet. 



— discoides, Ziet. 



— Tliouarsense, d^Orb. 



— striatulum, Sow. 



— radians, Reinecke. 



— Itaqiiinianum, d'Orb. 



— Levesquei, d'Orb. 



Cephalopoda. 



Harpoceras Leckenbyi, Lye. 



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



— variabile, d'Orb., var. dispansum, 



Lye. 



— obliquatum, Yomtg Sf Bird, the 



aged form of variabile. 

 Nautilus latidorsatus, d'Orb. 

 Belemnites compressus, J'olt:. 



— tripartitus, Schloth. 



— irregularis, Schloth. 



— Xodotianus, d'Orb. 



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