EXPLANATION OF PLATE LXXIII. 



Australian Polyplacophoba. 



Lepidoplt urus badius, Hedley & Hull. 



,, ,, median valve from within. 



Chiton roxi, Pilsbry. 



,, ,, sculpture of median valve. 



,, ,, posteiioi valve in profile. 



Chiton torri, Hedley it Hull. 



,, ,, sculpture of median valve. 



,, ,, interior of same. 



,. ,, posterior valve in profile. 



,, ,, interior of anterior valve. 



,, ,, interior of posterior valve. 



Chiton jugosus, Gould— sculpture of median valve. 



,, ,, posterior valve in profile. 



