CHAP, vin.] TEliTIAKY REPTILES. 105 



gives support to the tlieory of a great eastward extension of 

 Australia in Tertiary times. 



Extinct Tektiaf.y IiEptilks. 



These will not occupy us long, as no very great number are 

 known, find most of tliera l)eloiig to a few principal forms of 

 comparatively little geographical interest. 



Tortoises are perhaps the most abundant of the Tertiaiy 

 reptiles. They are numerous in the Eocene and jNIiocene 

 Ibrmations both in Europe and ISTorth America. The genera 

 Emus and Trionux abound in both countries, as well as in the 

 IMiocene of India. Land tortoises occur in the Eocene of Xorth 

 America and in the Miocene of Europe and India, where the 

 huge Colossochebjs, twelve feet long, has been found. In the 

 Pliocene deposits of Switzerland the living American genus 

 Chelydra has been met with. These facts, together with the 

 occurrence of a lining specks in the ]\Iiocene of India, show 

 that this order of reptiles is of great anticjuity, and that most 

 of the genera once had a wider range than now. 



Crocodiles, allied to the three forms now characteristic of 

 India, Africa, and America, have baen found in the Eocene of 

 our own country, and several species of Crocodilus have occurred 

 in beds of the same age in North America. 



Lizards are very ancient, many small terrestrial forms 

 occurring in all the Tertiary deposits. A species of the genus 

 Chamccleo is recorded from the Eocene of North America, to- 

 gether with several extinct genera. 



Snakes were well developed in the Eocene period, where 

 remains of several have been found which nnist have been from 

 twelve to twenty feet long. An extinct species of true viper has 

 occurred in the Miocene of Erance, and one of the Pythonidoe 

 in the Mioceiie brown coal of Germany. 



Batrachia occur but sparingly in a fossil state in the Ter- 

 tiary deposits. The most remarkable is the large Salamander 

 Andreas) from tlie Upper IMiocene of Switzorland, wliicli 



