638 



GEOLOGY. 



The order of succession in which the more important animals and plants started into 

 being, or the epoch of their creation, is stated in the following table from Professor 

 Brown. It should be distinctly observed, that their earliest appearance is here registered, 

 and not the aera of their prevalence. Thus the ichthyosaurus, here referred to the New 

 Red Sandstone period, flourished most abundantly in the subsequent oolitic period. 



CLAY SLATE AND SILURIAN PERIOD. 



Zoophytes. 



Marine shells. 



Crustacea, Trilobites. 



Fishes; Placoidians and Ganoidians (Sauroids and Sharks), also 

 those with heterocercal or unsymmetrical tails, the upper lobe 

 extending farther than the lower by the prolongation of the 

 vertebral column. 



Flowerless plants 1 Marine. 



Flowering plants ) Terrestrial. 



CARBONIFEROUS PERIOD. 



Fishes : Cephalaspis, &c. 



Arachnidans : Scorpions. 



Coleopterous insects. 



Fresh-water shells. 



Dicotyledonous plants : Coniferae (pines, &c.) Cycadese. 



Monocotyledonous plants : Palmze, Scitamineae. 



NEW RED SANDSTONE PERIOD. 



Tracks of birds, tortoises, and Chirotheria allied to Marsu- 



pialia. 

 Reptiles : Monitor, Phytosaurus, Ichthyosaurus, Plesiosaurus, 



Mastodonsaurus, Thecodontosaurus, Palasosaurus. 

 Crustacea : Palinurus. 

 Fishes: Palaseniscus, &c. 

 Dicotyledonous plants (Voltzia). 



OOLITIC PERIOD. 



Mammalia.' Thylacotherium. Cetacea: Phascolotherium (Didelphys 

 of Buckland). Reptiles: Saurocephalus, Saurodon, Teleosaurus, 

 Strepto-spondylus, Megalosaurus, Lacerta neptunia, ^Elodon, Rha- 

 cheosaurus, Pleurosaurus, Geosaurus, Macrospondylus, Pterodactylus, 

 Crocodile, Gavial, Tortoise. Fishes: Pycnodontes and Lepidoides, 

 ( Dapedium, &c. ) with homocercal tails. Arachnidans : Spiders. 

 Insects : Libellulae, Coleoptera. Crustacea : Pagurus, Eryon, Scyl- 

 larus, Palaemon, Astacus. Plants: Cycadea? ( Pterophyllum, 

 Zamia), Coniferae (Thuytes, Taxites), Lilia (Bucklandia). Birds : 

 Grallas (Tilgate Forest). Reptiles. Ifiuanodon, Leptorynchus, 

 Tryonix, Emys, Chelonia. Fishes : Lepidotus, Pycnodus, &c. 

 Fresh-water and estuarv shells. 



Encrinites Monilelormis. 





Ammonite Catena. 



CRETACEOUS PERIOD. 



Insects. 



Reptiles : Mososaurus, &c. 



Fishes .- Ctenoidians and Cycloidians. 



Crustacea : Arcania, Etyaea, Coryster. 



Plants : Confervas, Naiades. 



Turrilites Costatiis. 



Mocesamus Coucentricus. 



