671 THE NASAL ORGAN IN AMPHIBIA— HIGGINS 67 



preservation as far back as the Tertiary. Earlier than this all known fossil 

 forms are caudate, with the exception of a single specimen, Pelion lyelli, 

 found in the Carboniferous, which closely resembles recent Salientia. 

 Should Pelion prove to be a primitive Anuran, then the Urodeles and the 

 Anura have probably separated from the Stegocephalan ancestor as far 

 back as the late Devonian or early Carboniferous period. 



