EVOLUTION OF REPTILES. 



Relative Lengths of Epochs. 



TERTIARY. 1600 ft. 



CRETACEOUS. 2500 ft. 



JURASSIC. 5000 ft. 



TRIASSIC. 3000 ft. 



PERMIAN. 1500 ft. 



CARBONIFEROUS, 



12,000 ft. 



Earliest reptiles. Large amphibians. 

 20 to 30 million years ago. 



DEVONIAN. 4000 ft. 



Earliest amphibians, Lung fishes, Ganoid 



fishes. 



30 to 40 million years ago. 



SILURIAN. 



7000 ft. 



Primitive fishes. 

 40 to 50 million years 



ORDOVICIAN. 



15,000 ft. 



Earliest vertebrates. 

 50 to 65 million years ago. 



CAMBRIAN. 



12,000 ft. 



Invertebrates. 

 65 to 80 million years 



ARCH/EAN OR 

 PRE-CAMBRIAN. 



Extent unknown. 



No organic life. 



PLATE n. This diagram gives a rough 

 idea of the crust of the earth. The section 

 named Pre-Cambrian is partly composed of 

 the igneous fire-formed rocks. This is the 

 base or bottom strata. Below this is white- 

 hot liquid lava. 



The Cambrian is stratified rock. It was 

 formed after the earth was cool enough ifor 

 the gases in the air to condense and fall as 

 water on the earth. This water formed the 

 oceans. Stratified, or in other words Sedi- 

 mentary Rocks, are made by Sand, Silt, Ooze, 

 etc., falling to the bottoms of oceans, lakes, 

 and rivers. In this Cambrian formation we 

 find the first forms of organic life, such as 

 the very lowest types of aquatic creatures. 

 There is no trace of vegetation, fish, reptile, 

 bird, or animal life. 



As we enter the Ordovician, we find fossil 

 remains of Marine Scorpions, Crabs, and other 

 Crustaceans, but no fish or land life. 



Proceeding to the Silurian, we come across 

 traces of higher forms of ocean life, such as 

 the Silurian Fishes. As we emerge into the 

 Devonian we discover fossil remains in 

 abundance of the higher scaled fishes, with 

 true backbones and hard skeletons. Still 

 proceeding upward, we enter the great Car- 

 boniferous Period. It was during this Epoch 

 that the surface of the land was covered with 

 a vast growth of rapidly-growing vegetation 

 of fern-like and mossy nature. 



All vegetation grew with fungus-like 

 rapidity, without any periods of rest, for 

 there were no alternate hot and cold seasons 

 then. The earth itself and the waters were 

 warm and steaming ; the air was charged 

 with warm water vapour. 



This vegetation lived, died, formed thick 

 layers, and to-day we dig it up as coal and 

 burn it. It represents so much stored-up 

 heat, energy, and sunshine. This is how the 

 all-wise Creator provided for our needs. 



During the Carboniferous Period, the first 

 land animals began to evolve in the shape of 

 Amphibians, which developed later into true 

 reptiles. 



As we pass upward through the other 

 layers to the Earth's surface, we find reptiles 

 gradually evolving into warm - blooded 

 animals, such as birds and mammals. 



The most recent life upon our world is 

 Man, the Masterpiece. He is the latest pro- 

 duction, and the highest. To-day he is very 

 lowly in comparison to what he will be in ages 



It must be clearly understood the various 

 stratified rocks do not now lie evenly over one 

 another all over the earth. They are more 

 or less broken, tilted, cracked, and upheaved 

 by the intrusion and pressure of molten rock 

 from below, and the natural shrinkage due to 

 the progressive cooling of the Earth's crust. 



