% 
CATALOGUE 
OF 
FOSSIL FISHES. 
PAET IV. 
Order II. ACTINOPTERYGII {continued). 
Suborder IV. ISOSPONDYLl jcontinued) \ 
7a /9UQ 
Family - LEPTO LEPIDi E [ooHtinuul ]. y ^ 
Genus LYCOPTERA, J. MiiUer. C^) (> 
^ ' [Middendorff’s Sibirische Reise, vol. i. pt. i. 1848, p. 262.] 
Head large ; maxilla arched, with a slightly convex dentigerous 
border ; mandible prominent, the dentary gradually deepening from 
the symphysis backwards without any marked thickening; teeth 
minute and closely arranged. Opercular and branchiostegal appa¬ 
ratus apparently as in Leptolepis. Vertebral centra in form of 
delicate constricted cylinders. Pectoral fins much larger than the 
pelvic pair; dorsal fin small and short-based, opposite to the anal 
fin, which is not longer than deep ; caudal fin forked. Scales com¬ 
pletely covering the trunk, none enlarged or thickened. 
Recent researches seem to necessitate a modification of the definition of the 
Isospondyli given in Part III., p. 446, by the omission of the statements 
“ symplectic bone present” and “ precoi*acoid arch present.” The suborder is 
thus made to include the so called Scyphophori and Haplomi of Cope. Oon- 
vuA cerning the former (Mormyridse and Gyinnarchida) see Gr. A. Boulenger, Proc. 
Zool. Soc. 1898, pp. 775-821. 
PAET IV. 
