94 UPPER CRETACEOUS TELEOSTS 
ur2 
5mm 
Fic. 42. Enchodus marchesettii (Kramberger). Caudal fin skeleton in lateral view. 
vertebra I are fused with one another to produce a compound centrum which is 
slightly upturned. Articulating with this compound centrum are three structures, 
the parhypural, which represents the haemal spine of the first preural vertebra, 
and two hypural bones which extend up to the mid-line. The first hypural is the 
larger of the two, and basally bears a prominent fenestra. Dorsally the compound 
centrum bears an enlarged stegural element which projects postero-dorsally. The 
stegural bears an antero-dorsal expansion extending forwards towards the neural 
spine of the third preural vertebra. Posterior to the compound centrum ural 
vertebra 2 bears four hypurals, and may bear a second uroneural behind the postero- 
dorsal shaft of the stegural on the first ural vertebra. 
The caudal fin consists of 19 principal rays, 17 of which are branched. There 
are 10 shorter accessory rays dorsally and ventrally in advance of the principal 
caudal rays. 
Scales. The body is devoid of scales except for a row along the course of the 
lateral line and three reduced dermal scutes between the occiput and the dorsal fin. 
The line of scales marking the passage of the lateral line begins at the posterior region 
of the head of the supracleithrum, and extends along the whole length of the body, 
terminating on the lateral surface of the caudal peduncle. The row consists of 37 
scales, the same number of scales as vertebrae, and each one is roughly rectangular 
in shape with its posterior margin deeply excavated. Each individual scale is very 
small and is isolated from its neighbours. The surface of each scale bears an 
ornamentation of small ridges and a backwardly directed spine which projects over 
the anterior region of the deep indentation. The spine is very small on the anterior 
