AMIOIDEI 



335 



ring of many circumorbitals, several supratemporals, and a number of 

 email cheek-plates occur, but the median gular may be absent (Lepidotus). 



Fia. 315. 



Left-side view of the head of Dapedius. (After Traquair.) a, angular ; d, dentary ; co, ixwt- 

 orbital ; eth, ethmoid ; /, frontal ; g, median gular ; iop, interopercular ; mx, maxilla ; n. nostril ; 

 na, nasal ; op, opercular ; p, parietal ; rf, postfrontal ; pmx, premaxilla ; pop, preopercular ; 

 ps, supratemporal (?); pt, post- temporal ; pto, pterotic (squamosal) ; sd, supraclavicle ; w>, 

 cheek-plates ; sop, subopercular ; st, supratemporal. 



In these characters, and in the formation of an interorbital septum, and 

 especially in the position of the nostrils at the end of an elongated snout, 

 Lepidotus resembles the Lepidosteoidei. 



Fro. 316. 



Lepidotus minor, Ag. ; Upper Jurassic, Dorsetshire ; restored. (After A. S. Woodward, 

 Vert. Palaeontology.) 



The vertebral arches, spines, and ribs are well developed ; but the 

 notochord appears to have been persistent, at all events only ring-like 

 centra are found. The fulcra are large, in single or double rows, the 



