REPTILES. 
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placed far forward, with four toes; having internal lungs and 
persistant branchiae. 
Siren lacertina —The Siren. 
Plate LXXI. fig-. 5. 
Body black, speckled with white, eel-shaped ; white beneath ; 
sides wrinkled; tail provided with a soft adipose tin. Two feet 
long. Inhabits Carolina. 
FOSSIL REPTILES. 
Many different genera of fossil Reptiles have been discovered 
in various places of Europe, chiefly in the chalk formations ; of 
which we have figured two remarkable species, viz. :— 
Plesiosaurus. — Plate LXXIII. fig. 1.—An animal ap¬ 
proaching near to the crocodile in form, but having double the 
number of vertebrae; its neck resembles the body of a serpent, 
its head that of a lizard ; and in place of feet has fin-like swim¬ 
ming apparatus like those of whales. 
Ichthyosaurus.— Plate LXXIII. fig. 2_ This recedes 
from the lizard trihe, and approaches in form to that of a fish, 
in the structure of its vertebral colume, and has paddle-shaped 
membranes for progression; it has the snout of a dolphin, the 
teeth of a crocodile, the head and sternum of a lizard, and pad¬ 
dles of a whale. Forty feet long. Found in the lias and Oxford 
clay, &c. 
