528 STRATIGRAPHICAL GEOLOGY 



the palrns Nipa, Sabal, and Areca ; the Dicotyledons Ficus, 

 Aralia, Dryandra, Cassia, Eucalyptus, Magnolia, Cactus, and many 

 kinds of Leguminosce. In the Bournemouth Beds a still larger 

 number occur, and form a different assemblage, but still one of 

 sub-tropical aspect ; this includes ferns of the genera Osmunda, 

 Chrysodium, Pteris, and Gleichenia, the palms Sabal, Iriartea, 

 Flabellaria, Phcenicites, and a large number of Dicotyledonous leaf 

 impressions which have not yet been properly determined. 



Of invertebrate animals the following are the principal genera 

 which now make their appearance in Britain, though some of 

 them (particularly the Gastropods) really date from the Upper 

 Cretaceous Beds of Europe : 



Protozoa. Alveolina, Nummulites. 



Actinozoa. Balanophyllia, Dendrophyllia, Goniopora ( = Litharea), 



Madrepora, Oculina, Paracyathus, Solenastrea, 



Turbinolia. 



Echinoderma. Schizaster, Spatangus. 



Crustacea. Dromia, Mithracia, Portunites, Xanthopsis. 



Lamellibranchia. Corbicula, Diplodonta, Potamomya, Sanguinolaria, 



Verticordia. 

 Gastropoda. Ancilla, Cassis, Conus, Conorbis, Cyprsea, Fasciolaria, 



Marginella, Oliva, Pyrula, Rostellaria, Rimella, 



Sycum ( = Leiostoma), Tritonium, Trophon, Typhis, 



Yoluta, Xenophora. 

 Cephalopoda. Aturia, Beloptera, Belosepia. 



Vertebrate animals are now abundant, the four great classes of 

 fish, birds, reptiles, and mammals being all represented, though 

 remains of birds are rare. The following are some of the genera 

 found in the Eocene Series of England and France : 



Pisces. Myliobatis, jEtobatis, Pristis ; Lepidosteus, Phyllodus ; 



Ccelopoma, Goniognathus, Sphyrsenodus ( = Dictyo- 



dus) ; Percostoma, Scisenurus, and others. 

 Reptilia. Gavialis (a crocodile) ; Lacerta (a lizard) ; Palseophis 



(a sea-snake) ; Trionyx, Lytoloma, Argillochelys 



(tortoises). 

 Aves. Argillornis, Dasornis, Gastornis, Halcyornis, Eupter- 



ornis, Lithornis, Odontopteryx, all large birds. 



Odontopteryx had a large beak furnished with 



tooth-like processes. 



Mammalia. These deserve more special description. Mar- 

 supials of the genus Didelphys were common, and with these 

 are carnivores (Arctocyon and Palceonictis) with strong marsupial 

 affinities, but believed to be really placentals ; a little later appear 

 other carnivora, Pterodon, and Proviverra. The earliest known 

 ungulate is Coryphodon, a primitive tapir from the Woolwich Be 3s 

 and London Clay. Still later other genera appeared, Lophiodon, 



