DISTRIBUTION OF THE MIDDLE LIAS AMMONITES. 



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A Table showing the stratigraphical distribution of the Ammonoida in the Middle Lias of 



the British Islands. 



Families, 



Geneka, and Species. 



Family — Aegockratid^. 

 Genus — Akgoceras. 



Aegoceras armatum. Sow 



— densinodum, Quenst. 



— siibmuticu m , Oppel 



— Jamesoni, Soto 



— brevispitmm, /iSb2£7 



— Taylori, Sow 



— pettos, Quenst 



— Valdani, d' Orbig 



— Maugenesti, d' Orbig 



— Henleyi, /Sbyy 



— striatum, Reinecke 



— Becliei, /So^fj 



— cwW\CQx\\wa\, Schlonh 



— Davoei, /Sbw 



Family — Arcestid^e. 

 Genus — Am altheu s . 



Amaltheus Ibex, Quenst 



— margaritatus, J/o??//'. 



— Engelhardti, d^ Orbig 



— spinatus, Brug 



Family — Lytoceratid^. 

 Genus — Phylloceras. 



Phylloceras Loscombi, Sow 



— Zeie?,, d^ Orbig 



Ge7ius — Lttoceras. 



Lytoceras fimbriatum, Sow 



— lineatum, Schloth 



^ In this table I have separated the Armatum from the Jamesoni zone, because Aeg. armatum and its 

 allied forms are limited in their range to the lowest portion of the latter, and are the most characteristic 

 fossils of the basement bed of the Middle Lias. 



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