CHAP. VIII.] 
TERTIARY REPTILES. 
165 
gives support to the theory of a great eastward extension of 
Australia in Tertiary times. 
Extinct Tertiary Reptiles. 
These will not occupy us long, as no very great number are 
known, and most of them belong to a few principal forms of 
comparatively little geographical interest. 
Tortoises are perhaps the most abundant of the Tertiary 
reptiles. They are numerous in the Eocene and Miocene 
formations both in Europe and North America. The genera 
Emys and Trionyx abound in both countries, as well as in the 
Miocene of India. Land tortoises occur in the Eocene of North 
America and in the Miocene of Europe and India, where the 
huge Colossochdys, 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 living species in the Miocene of India, show 
that this order of reptiles is of great antiquity, 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 been 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 
Ckamceleo 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 must 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 Pythonidse 
in the Miocene 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 the Upper Miocene of Switzerland, which 
