546 TELEOSTEI CHAP. 
Fam. 4. Leptolepididae.—Praemaxillaries very small; maxil- 
laries large, loosely attached ; teeth small and conical. Parietal 
bones separating the supraoccipital from the frontals; opercular 
bones well developed. Vertebral centra well ossified, but always 
pierced by the notochord; ribs delicate ; epipleurals present ; no 
fused or expanded haemal arches at the base of the caudal 
fin. Dorsal and anal fins small, the former above or behind the 
ventrals. Ventrals with 5 to 10 rays. Scales thin, cycloid and 
deeply imbricate, usually coated with ganoin in their exposed 
portion. 
fj ii) ’ 
Y Auth 
Fic. 325.—Leptolepis dubius. (Restoration of skeleton by A. 8. Woodward. ) 
Leptolepis, with numerous species, from the Jurassic and Cre- 
taceous of Europe and New South Wales; Vidalia, Jurassic of 
France; Aethalion, Jurassic of Bavaria; Zhrissops, Jurassic and 
Cretaceous of Europe; and Lycoptera, Jurassic of Asia. 
Fam. 5. Elopidae——Margin of the upper jaw formed by the 
praemaxillaries and the maxillaries, the latter the more developed, 
and movably articulated above the former to the ethmoid. 
Parietal bones in contact behind the frontals: opercular bones 
well developed. Basis crani double. A bony intergular or 
sublingual plate. Jaws, palatines, pterygoids, vomer, para- 
sphenoid, glossohyal, and pharyngeals toothed. Ribs mostly 
sessile, inserted very low down, behind parapophyses ; epineurals 
similar to the ribs, but directed upwards. Pectorals low down, 
folding like the ventrals. Post-temporal forked, the upper 
branch attached to the epiotic, the lower to the opisthotic ; 
postgelavicle small; scapular foramen in the scapula; pterygials 
wel developed, three in contact with coracoid. Ventrals with 
10 to 16 rays. Branchiostegal rays very numerous (over 20). 
Air-bladder large. 
