208 
THE LIAS AMMONITES. 
Lamarck, 1799. = Angiilitlies, Montfort, 1808. = Oceanus, Montfort, 1808. 
= Ammonites {pars), Montfort, 1808. = Bisiphites {pars), Montfort, 1808. = Con- 
chyliolithus, Martin, 1809. — Ammonellipsites, Parkinson, 1811. — Ellipsolithes 
{pars), Sowerby, 1812. = Uliabdites, de Haan, 1825. = Omphalia, de Haan, 
1825. = Globites, de Haan, 1825. = Aganides {pars), d'Orbigny, 1826. = 
Aganites {pars), Quenstedt, 1834. = Aturia {pars), Bronn, 1835. = Hamites 
{pars), Fischer, 1837. — Trocholites {pars), Conrad, 1838. = Simplegas {pars), 
Sowerby, 1842. = Discites {pars), M'Coy, 1844. = Discus {pars). King, 1844. 
= Cryptoceras {pars), d'Orbigny, 1850. = Trematodiscus {pars), Meek, 1861. 
Turns {whorls) of the shell, in contact, partially overlapping ; siphuncle almost cen- 
tral ; aperture of exterior chamber open without folds ; Silurian into Tertiary, still 
living. 
Rhyncholithes, Eaure-Biguet, 1819, = Conchorhynchus, De Blainville, 1827. 
=: Rhynchoteuthis, d'Orbigny, 1847. 
Comprising the beaks of the Nautilus animal. 
22. DiscocEEAs, Barrande, 1867. 
Turns of the shell touching, siphuncle variable ; aperture of exterior chamber open, 
its edge not contracted ; Silurian. 
23. Ophidioceras, Barrande, 1867. 
Turns of the shell touching ; siphuncle variable ; aperture of exterior chamber con- 
tracted; Silurian. 
24. Gyroceras, de Koninck, 1844. = Gyroceratites, H. von Meyer, 1829. 
= Hortolus, Steininger, 1831. = Spirula, Goldfuss, 1832. = Lituites, Quenstedt, 
1834. = Cyrtocera {pars), Miinster, 1839. = Cyrtoceras {pars), Phillips, 1841. 
= Cyrthoceratites {pars), D'Archiac, 1842. 
Turns of the shell not in contact ; siphuncle marginal on external (convex) side ; 
last chamber somewhat small, edge without fold ; from Silurian into Carboniferous. 
2. Shell an arc of a spiral, in the same plane. 
25. Cyrtoceras, Goldfuss, 1832. = Orthoceratites, Lamarck, 1799. = Ortho- 
cera {pars), Sowerby, 1812. = Campulites, Deshayes, 1832. = Lituites {pars), 
Quenstedt, 1836. = Cyrtoceratites, d'Archiac, 1842. — Trigonoceras, M'Coy, 1844. 
= Campyloceras, M'Coy, 1844. = Aploceras, d'Orbigny, 1850. 
