1893.] 



OSTEOLOGY OF LEPIDOTtJS AXD DAPEDIUS. 



• 561 



The membrane-bones of the cranial roof do not extend backwards 

 quite so far as the occipital border, the narrow space thus left 

 being covered by the supratemporal plates. There are two prin- 

 cipal pairs of bones, the short parietals (Plate XLIX. fig. 1, pa.) 

 behind, and the longer frontals (fr.) forwards, not bilaterally 

 symmetrical, and uniting in all directions by very irregular au- 

 gulated sutui'es. More anteriorly there would be the nasals, but 



Head-bones of Lepidotus lafifroiis ; Oxford Cla}', Peterborough. 

 Oue half nat. size. 



1. Exoccipital. 2. Pro-otic. 3. Paraspbenoid, inferior aspect. 3 a. Para- 

 sphenoid, superior aspect. 4. Eight quadrate, inner aspect. 5. Left 

 quadrate, outer aspect. 6. Metapterj'goid. 



hpt., basipterygoid process ; /., foramen ; x>., process. 



these are not satisfactorily known. The long and narrow squa- 

 mosal element {sq.) on each side reaches as far forwards as the 

 anterior extremity of the parietals, but not so far backwards as 

 the hinder margin of these bones. It is considerably overlapped 

 behind by the supratemporal series of plates, and on the inner 



