8. Order: Clupeiformes
• Well developed cycloid scales.
• Homocercal caudal fin.
• Werberian apparatus present.
• Air bladder connected with ear.
• Eg: Salmo
9. Class: Scopeliformes
• Presence of second dorsal fin
or adipose fin.
• Usually luminous organs present.
• Mouth with numerous teeth.
• Swim bladder absent.
• Eg: Harpodon
10. Class: Cypriniformes
• Air bladder with duct to
Pharynx.
• Werberian ossicles present
connecting ear and Air bladder.
• Air bladder also connected with
Alimentary canal.
• Eg: Labio
11. Class: Anguiliiformes
• Snake like fish.
• Scales vestigial or absent.
• Long dorsal and anal fin.
• Air bladder connected with intestine.
• Anguilla
12. Class: Beloniformes
• Elongated body.
• Cycloid scales.
• Ventral fins shifted to abdominal
sides.
• Some can fly.
• Exocoetus, Cypselurus
15. Class: Symbranchiformes
• Sym- jointed, branchia- gills.
• Eel like body.
• Gill slits jointed to form
transverse ventral slites.
• No air bladder.
• Symbranchus
16. Class: Mastacembeliformes
• Eel like body.
• Free spines infront of dorsal fin.
• Dorsal, anal and caudal fins united
to form A continuous fin.
• Mastacembelus
17. Class: Perciformes
• Perci- spines.
• Fins with spines.
• 2 dorsal fins.
• Werberian apparatus absent.
• Air bladder without duct.
• Anabas