TABLE OP CHAEACTEEISTIC GENERA. 



123 



II. TABLE OF CHAEACTEEISTIC GENEEA. 



Systems. 



Genera and Sub- genera. 



1. C AMEBIAN, or 

 Lower Silurian 



2. Silurian 



3. Devonian 



4. Cabboniferous... 



5. Permian 



/ Camaroceras, Endoceras, Gonioceras, Pterotheca. 

 J Maclurea, Kaphistoma, Holopea, Platyceras. 

 j Orthisina, Platystrophia, Porambonites, Pseudo- crania. 

 (^Ambonycliia, Modiolopsis, Lyrodesma. 



1 Actinoceras, Phr^^gmoceras, Trochoceras, Ascoceras. 

 ' Theca, Holopella, Murchisonia, Atrypa, Retzia. 

 ( Cardiola, Clidophorus, Goniophorus, Grammysia. 



[ Bactrites, Gyroceras, Clymenia, Apioceras, Serpularia. 

 < Sprrifera, Uncites, Merista, Davidsonia, Calceola. 

 ( Stringocephalus, Megalodou, Orthonota, Pterinea. 



I Nautiloceras, Discites, Goniatites, Porcellia. 



J Naticopsis, Platyschisma, Metoptoma, Productus. 



( Aviculo-pecten, Anthracosia, Conocardium, Sedgwickia. 



3 Camarophoria, Aulosteges, Strophalosia. 

 (Myalina, Bakewellia, Axinus, Edmondia. 



6. Tkias 



7. L. Jurassic 



8. U. Jurassic 



9. L. Cretaceous ... 

 10. U. Cretaceous ... 



f Ceratites, Naticella, Platystoma, Koninckia, Cyrtia. 

 \ Monotis, Myophoria, Pleurophorus, Opis. 



/'Belemnites, Beloteuthis, Geoteuthis, Ammonites. 

 J Alaria, Trochotonui, Eimula, Pileolus, Cylindrites. 

 J Waldheimia, Tkecldium, Spiiiferina, Ceromya. 

 (_Gryphsea, Hippopodium, Cardinia, Mycconcha. 



/" Coccoteuthis, Leptoteuthis, Nautilus. 

 1 Spinigera, Purpurina, Nerinsea, Neritoma. 

 J Pteroperna, Trichites, Hypotrema, Diceras. 

 (_ Trigonia, Pachyrisma, Sowerbia, Tancredia. 



i Crioceras, Toxoceras, Hamulina, Baculina. 

 l Requienia, Caprinella, Sphsera, Thetis. 



/Belemnitella, Conoteuthis, Turrilites, Ptychoceras. 

 J Hamites, Scaphites, Pterodonta, Cinulia, Tylostoma. 

 J Acteonella, Globiconcha, Trigonosemus, Magas, Lyra. 

 (^Neithea, Inoceramus, Hippurites, Caprina, Caprotina. 



11. Eocene 



1 



12. Miocene 



/Belopiera, Lychnus, Megaspira, Glandina, Typhis. 

 ) Volutilithes, Clavella, Pseudoliva, Seraphs, Bimella, 

 "S Conorbis, Strepsidura, Globulus, Phxyrus, Velates. 

 (Chilostoma, Volvaria, Lithocardium, Teredina. 



i Spirulirostra, Aturia, Vaginella, Ferussina. 



J Halia, Proto, Deshayesia, Niso, Cassidaria, Carolia. 



( Grateloupia, Artemis, Tapes, Jouannetia. 



f Argonauta, Strombus, Purpura, Trophon. 

 \ ioldia, Tridacna, Circe, Verticordia, 



13 Pliocene 





G 2 



